Update fullsdk to 4575844

/google/data/ro/projects/android/fetch_artifact \
    --bid 4575844 \
    --target sdk_phone_x86_64-sdk \
    sdk-repo-linux-sources-4575844.zip

Test: TreeHugger
Change-Id: I81e0eb157b4ac3b38408d0ef86f9d6286471f87a

8 files changed, 969 insertions, 240 deletions

diff --git a/android/view/accessibility/AccessibilityEvent.java b/android/view/accessibility/AccessibilityEvent.java
index 1d19a9f5..e0f74a7d 100644
--- a/android/view/accessibility/AccessibilityEvent.java
+++ b/android/view/accessibility/AccessibilityEvent.java
@@ -38,19 +38,14 @@ import java.util.List;
  * <p>
  * An accessibility event is fired by an individual view which populates the event with
  * data for its state and requests from its parent to send the event to interested
- * parties. The parent can optionally add an {@link AccessibilityRecord} for itself before
- * dispatching a similar request to its parent. A parent can also choose not to respect the
- * request for sending an event. The accessibility event is sent by the topmost view in the
- * view tree. Therefore, an {@link android.accessibilityservice.AccessibilityService} can
- * explore all records in an accessibility event to obtain more information about the
- * context in which the event was fired.
+ * parties. The parent can optionally modify or even block the event based on its broader
+ * understanding of the user interface's context.
  * </p>
  * <p>
- * The main purpose of an accessibility event is to expose enough information for an
- * {@link android.accessibilityservice.AccessibilityService} to provide meaningful feedback
- * to the user. Sometimes however, an accessibility service may need more contextual
- * information then the one in the event pay-load. In such cases the service can obtain
- * the event source which is an {@link AccessibilityNodeInfo} (snapshot of a View state)
+ * The main purpose of an accessibility event is to communicate changes in the UI to an
+ * {@link android.accessibilityservice.AccessibilityService}. The service may then inspect,
+ * if needed the user interface by examining the View hierarchy, as represented by a tree of
+ * {@link AccessibilityNodeInfo}s (snapshot of a View state)
  * which can be used for exploring the window content. Note that the privilege for accessing
  * an event's source, thus the window content, has to be explicitly requested. For more
  * details refer to {@link android.accessibilityservice.AccessibilityService}. If an
@@ -85,21 +80,6 @@ import java.util.List;
  *   <li>{@link #getClassName()} - The class name of the source.</li>
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
  *   <li>{@link #getEventTime()}  - The event time.</li>
- *   <li>{@link #getText()} - The text of the source's sub-tree.</li>
- *   <li>{@link #isEnabled()} - Whether the source is enabled.</li>
- *   <li>{@link #isPassword()} - Whether the source is password.</li>
- *   <li>{@link #isChecked()} - Whether the source is checked.</li>
- *   <li>{@link #getContentDescription()} - The content description of the source.</li>
- *   <li>{@link #getScrollX()} - The offset of the source left edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getScrollY()} - The offset of the source top edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getFromIndex()} - The zero based index of the first visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getToIndex()} - The zero based index of the last visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getItemCount()} - The total items of the source
- *       (for descendants of AdapterView).</li>
  * </ul>
  * </p>
  * <p>
@@ -113,21 +93,6 @@ import java.util.List;
  *   <li>{@link #getClassName()} - The class name of the source.</li>
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
  *   <li>{@link #getEventTime()}  - The event time.</li>
- *   <li>{@link #getText()} - The text of the source's sub-tree.</li>
- *   <li>{@link #isEnabled()} - Whether the source is enabled.</li>
- *   <li>{@link #isPassword()} - Whether the source is password.</li>
- *   <li>{@link #isChecked()} - Whether the source is checked.</li>
- *   <li>{@link #getContentDescription()} - The content description of the source.</li>
- *   <li>{@link #getScrollX()} - The offset of the source left edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getScrollY()} - The offset of the source top edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getFromIndex()} - The zero based index of the first visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getToIndex()} - The zero based index of the last visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getItemCount()} - The total items of the source
- *       (for descendants of AdapterView).</li>
  * </ul>
  * </p>
  * <p>
@@ -141,23 +106,6 @@ import java.util.List;
  *   <li>{@link #getClassName()} - The class name of the source.</li>
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
  *   <li>{@link #getEventTime()}  - The event time.</li>
- *   <li>{@link #getText()} - The text of the source's sub-tree.</li>
- *   <li>{@link #isEnabled()} - Whether the source is enabled.</li>
- *   <li>{@link #isPassword()} - Whether the source is password.</li>
- *   <li>{@link #isChecked()} - Whether the source is checked.</li>
- *   <li>{@link #getItemCount()} - The number of selectable items of the source.</li>
- *   <li>{@link #getCurrentItemIndex()} - The currently selected item index.</li>
- *   <li>{@link #getContentDescription()} - The content description of the source.</li>
- *   <li>{@link #getScrollX()} - The offset of the source left edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getScrollY()} - The offset of the source top edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getFromIndex()} - The zero based index of the first visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getToIndex()} - The zero based index of the last visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getItemCount()} - The total items of the source
- *       (for descendants of AdapterView).</li>
  * </ul>
  * </p>
  * <p>
@@ -171,23 +119,6 @@ import java.util.List;
  *   <li>{@link #getClassName()} - The class name of the source.</li>
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
  *   <li>{@link #getEventTime()}  - The event time.</li>
- *   <li>{@link #getText()} - The text of the source's sub-tree.</li>
- *   <li>{@link #isEnabled()} - Whether the source is enabled.</li>
- *   <li>{@link #isPassword()} - Whether the source is password.</li>
- *   <li>{@link #isChecked()} - Whether the source is checked.</li>
- *   <li>{@link #getItemCount()} - The number of focusable items on the screen.</li>
- *   <li>{@link #getCurrentItemIndex()} - The currently focused item index.</li>
- *   <li>{@link #getContentDescription()} - The content description of the source.</li>
- *   <li>{@link #getScrollX()} - The offset of the source left edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getScrollY()} - The offset of the source top edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getFromIndex()} - The zero based index of the first visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getToIndex()} - The zero based index of the last visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getItemCount()} - The total items of the source
- *       (for descendants of AdapterView).</li>
  * </ul>
  * </p>
  * <p>
@@ -201,15 +132,11 @@ import java.util.List;
  *   <li>{@link #getClassName()} - The class name of the source.</li>
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
  *   <li>{@link #getEventTime()}  - The event time.</li>
- *   <li>{@link #getText()} - The text of the source.</li>
- *   <li>{@link #isEnabled()} - Whether the source is enabled.</li>
- *   <li>{@link #isPassword()} - Whether the source is password.</li>
- *   <li>{@link #isChecked()} - Whether the source is checked.</li>
+ *   <li>{@link #getText()} - The new text of the source.</li>
+ *   <li>{@link #getBeforeText()} - The text of the source before the change.</li>
  *   <li>{@link #getFromIndex()} - The text change start index.</li>
  *   <li>{@link #getAddedCount()} - The number of added characters.</li>
  *   <li>{@link #getRemovedCount()} - The number of removed characters.</li>
- *   <li>{@link #getBeforeText()} - The text of the source before the change.</li>
- *   <li>{@link #getContentDescription()} - The content description of the source.</li>
  * </ul>
  * </p>
  * <p>
@@ -223,13 +150,6 @@ import java.util.List;
  *   <li>{@link #getClassName()} - The class name of the source.</li>
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
  *   <li>{@link #getEventTime()}  - The event time.</li>
- *   <li>{@link #getText()} - The text of the source.</li>
- *   <li>{@link #isPassword()} - Whether the source is password.</li>
- *   <li>{@link #getFromIndex()} - The selection start index.</li>
- *   <li>{@link #getToIndex()} - The selection end index.</li>
- *   <li>{@link #getItemCount()} - The length of the source text.</li>
- *   <li>{@link #isEnabled()} - Whether the source is enabled.</li>
- *   <li>{@link #getContentDescription()} - The content description of the source.</li>
  * </ul>
  * </p>
  * <b>View text traversed at movement granularity</b> - represents the event of traversing the
@@ -251,23 +171,11 @@ import java.util.List;
  *   <li>{@link #getToIndex()} - The end of the text that was skipped over in this movement.
  *       This is the ending point when moving forward through the text, but not when moving
  *       back.</li>
- *   <li>{@link #isPassword()} - Whether the source is password.</li>
- *   <li>{@link #isEnabled()} - Whether the source is enabled.</li>
- *   <li>{@link #getContentDescription()} - The content description of the source.</li>
- *   <li>{@link #getMovementGranularity()} - Sets the granularity at which a view's text
- *       was traversed.</li>
  *   <li>{@link #getAction()} - Gets traversal action which specifies the direction.</li>
  * </ul>
  * </p>
  * <p>
- * <b>View scrolled</b> - represents the event of scrolling a view. If
- * the source is a descendant of {@link android.widget.AdapterView} the
- * scroll is reported in terms of visible items - the first visible item,
- * the last visible item, and the total items - because the the source
- * is unaware of its pixel size since its adapter is responsible for
- * creating views. In all other cases the scroll is reported as the current
- * scroll on the X and Y axis respectively plus the height of the source in
- * pixels.</br>
+ * <b>View scrolled</b> - represents the event of scrolling a view. </br>
  * <em>Type:</em> {@link #TYPE_VIEW_SCROLLED}</br>
  * <em>Properties:</em></br>
  * <ul>
@@ -276,37 +184,19 @@ import java.util.List;
  *   <li>{@link #getClassName()} - The class name of the source.</li>
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
  *   <li>{@link #getEventTime()}  - The event time.</li>
- *   <li>{@link #getText()} - The text of the source's sub-tree.</li>
- *   <li>{@link #isEnabled()} - Whether the source is enabled.</li>
- *   <li>{@link #getContentDescription()} - The content description of the source.</li>
- *   <li>{@link #getScrollX()} - The offset of the source left edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getScrollY()} - The offset of the source top edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getFromIndex()} - The zero based index of the first visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getToIndex()} - The zero based index of the last visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getItemCount()} - The total items of the source
- *       (for descendants of AdapterView).</li>
+ *   <li>{@link #getScrollDeltaX()} - The difference in the horizontal position.</li>
+ *   <li>{@link #getScrollDeltaY()} - The difference in the vertical position.</li>
  * </ul>
- * <em>Note:</em> This event type is not dispatched to descendants though
- * {@link android.view.View#dispatchPopulateAccessibilityEvent(AccessibilityEvent)
- * View.dispatchPopulateAccessibilityEvent(AccessibilityEvent)}, hence the event
- * source {@link android.view.View} and the sub-tree rooted at it will not receive
- * calls to {@link android.view.View#onPopulateAccessibilityEvent(AccessibilityEvent)
- * View.onPopulateAccessibilityEvent(AccessibilityEvent)}. The preferred way to add
- * text content to such events is by setting the
- * {@link android.R.styleable#View_contentDescription contentDescription} of the source
- * view.</br>
  * </p>
  * <p>
  * <b>TRANSITION TYPES</b></br>
  * </p>
  * <p>
- * <b>Window state changed</b> - represents the event of opening a
- * {@link android.widget.PopupWindow}, {@link android.view.Menu},
- * {@link android.app.Dialog}, etc.</br>
+ * <b>Window state changed</b> - represents the event of a change to a section of
+ * the user interface that is visually distinct. Should be sent from either the
+ * root view of a window or from a view that is marked as a pane
+ * {@link android.view.View#setAccessibilityPaneTitle(CharSequence)}. Not that changes
+ * to true windows are represented by {@link #TYPE_WINDOWS_CHANGED}.</br>
  * <em>Type:</em> {@link #TYPE_WINDOW_STATE_CHANGED}</br>
  * <em>Properties:</em></br>
  * <ul>
@@ -315,8 +205,7 @@ import java.util.List;
  *   <li>{@link #getClassName()} - The class name of the source.</li>
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
  *   <li>{@link #getEventTime()}  - The event time.</li>
- *   <li>{@link #getText()} - The text of the source's sub-tree.</li>
- *   <li>{@link #isEnabled()} - Whether the source is enabled.</li>
+ *   <li>{@link #getText()} - The text of the source's sub-tree, including the pane titles.</li>
  * </ul>
  * </p>
  * <p>
@@ -325,10 +214,6 @@ import java.util.List;
  * a view size, etc.</br>
  * </p>
  * <p>
- * <strong>Note:</strong> This event is fired only for the window source of the
- * last accessibility event different from {@link #TYPE_NOTIFICATION_STATE_CHANGED}
- * and its purpose is to notify clients that the content of the user interaction
- * window has changed.</br>
  * <em>Type:</em> {@link #TYPE_WINDOW_CONTENT_CHANGED}</br>
  * <em>Properties:</em></br>
  * <ul>
@@ -339,32 +224,26 @@ import java.util.List;
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
  *   <li>{@link #getEventTime()}  - The event time.</li>
  * </ul>
- * <em>Note:</em> This event type is not dispatched to descendants though
- * {@link android.view.View#dispatchPopulateAccessibilityEvent(AccessibilityEvent)
- * View.dispatchPopulateAccessibilityEvent(AccessibilityEvent)}, hence the event
- * source {@link android.view.View} and the sub-tree rooted at it will not receive
- * calls to {@link android.view.View#onPopulateAccessibilityEvent(AccessibilityEvent)
- * View.onPopulateAccessibilityEvent(AccessibilityEvent)}. The preferred way to add
- * text content to such events is by setting the
- * {@link android.R.styleable#View_contentDescription contentDescription} of the source
- * view.</br>
  * </p>
  * <p>
- * <b>Windows changed</b> - represents the event of changes in the windows shown on
+ * <b>Windows changed</b> - represents a change in the windows shown on
  * the screen such as a window appeared, a window disappeared, a window size changed,
- * a window layer changed, etc.</br>
+ * a window layer changed, etc. These events should only come from the system, which is responsible
+ * for managing windows. The list of windows is available from
+ * {@link android.accessibilityservice.AccessibilityService#getWindows()}.
+ * For regions of the user interface that are presented as windows but are
+ * controlled by an app's process, use {@link #TYPE_WINDOW_STATE_CHANGED}.</br>
  * <em>Type:</em> {@link #TYPE_WINDOWS_CHANGED}</br>
  * <em>Properties:</em></br>
  * <ul>
  *   <li>{@link #getEventType()} - The type of the event.</li>
  *   <li>{@link #getEventTime()} - The event time.</li>
+ *   <li>{@link #getWindowChanges()}</li> - The specific change to the source window
  * </ul>
  * <em>Note:</em> You can retrieve the {@link AccessibilityWindowInfo} for the window
- * source of the event via {@link AccessibilityEvent#getSource()} to get the source
- * node on which then call {@link AccessibilityNodeInfo#getWindow()
- * AccessibilityNodeInfo.getWindow()} to get the window. Also all windows on the screen can
- * be retrieved by a call to {@link android.accessibilityservice.AccessibilityService#getWindows()
- * android.accessibilityservice.AccessibilityService.getWindows()}.
+ * source of the event by looking through the list returned by
+ * {@link android.accessibilityservice.AccessibilityService#getWindows()} for the window whose ID
+ * matches {@link #getWindowId()}.
  * </p>
  * <p>
  * <b>NOTIFICATION TYPES</b></br>
@@ -402,19 +281,6 @@ import java.util.List;
  *   <li>{@link #getClassName()} - The class name of the source.</li>
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
  *   <li>{@link #getEventTime()}  - The event time.</li>
- *   <li>{@link #getText()} - The text of the source's sub-tree.</li>
- *   <li>{@link #isEnabled()} - Whether the source is enabled.</li>
- *   <li>{@link #getContentDescription()} - The content description of the source.</li>
- *   <li>{@link #getScrollX()} - The offset of the source left edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getScrollY()} - The offset of the source top edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getFromIndex()} - The zero based index of the first visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getToIndex()} - The zero based index of the last visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getItemCount()} - The total items of the source
- *       (for descendants of AdapterView).</li>
  * </ul>
  * </p>
  * <b>View hover exit</b> - represents the event of stopping to hover
@@ -428,19 +294,6 @@ import java.util.List;
  *   <li>{@link #getClassName()} - The class name of the source.</li>
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
  *   <li>{@link #getEventTime()}  - The event time.</li>
- *   <li>{@link #getText()} - The text of the source's sub-tree.</li>
- *   <li>{@link #isEnabled()} - Whether the source is enabled.</li>
- *   <li>{@link #getContentDescription()} - The content description of the source.</li>
- *   <li>{@link #getScrollX()} - The offset of the source left edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getScrollY()} - The offset of the source top edge in pixels
- *       (without descendants of AdapterView).</li>
- *   <li>{@link #getFromIndex()} - The zero based index of the first visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getToIndex()} - The zero based index of the last visible item of the source,
- *       inclusive (for descendants of AdapterView).</li>
- *   <li>{@link #getItemCount()} - The total items of the source
- *       (for descendants of AdapterView).</li>
  * </ul>
  * </p>
  * <p>
@@ -513,10 +366,10 @@ import java.util.List;
  * <b>MISCELLANEOUS TYPES</b></br>
  * </p>
  * <p>
- * <b>Announcement</b> - represents the event of an application making an
- * announcement. Usually this announcement is related to some sort of a context
- * change for which none of the events representing UI transitions is a good fit.
- * For example, announcing a new page in a book.</br>
+ * <b>Announcement</b> - represents the event of an application requesting a screen reader to make
+ * an announcement. Because the event carries no semantic meaning, this event is appropriate only
+ * in exceptional situations where additional screen reader output is needed but other types of
+ * accessibility services do not need to be aware of the change.</br>
  * <em>Type:</em> {@link #TYPE_ANNOUNCEMENT}</br>
  * <em>Properties:</em></br>
  * <ul>
@@ -526,7 +379,6 @@ import java.util.List;
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
  *   <li>{@link #getEventTime()}  - The event time.</li>
  *   <li>{@link #getText()} - The text of the announcement.</li>
- *   <li>{@link #isEnabled()} - Whether the source is enabled.</li>
  * </ul>
  * </p>
  *
@@ -586,8 +438,10 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
     public static final int TYPE_VIEW_TEXT_CHANGED = 0x00000010;
 
     /**
-     * Represents the event of opening a {@link android.widget.PopupWindow},
-     * {@link android.view.Menu}, {@link android.app.Dialog}, etc.
+     * Represents the event of a change to a visually distinct section of the user interface.
+     * These events should only be dispatched from {@link android.view.View}s that have
+     * accessibility pane titles, and replaces {@link #TYPE_WINDOW_CONTENT_CHANGED} for those
+     * sources. Details about the change are available from {@link #getContentChangeTypes()}.
      */
     public static final int TYPE_WINDOW_STATE_CHANGED = 0x00000020;
 
@@ -674,7 +528,8 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
     public static final int TYPE_TOUCH_INTERACTION_END = 0x00200000;
 
     /**
-     * Represents the event change in the windows shown on the screen.
+     * Represents the event change in the system windows shown on the screen. This event type should
+     * only be dispatched by the system.
      */
     public static final int TYPE_WINDOWS_CHANGED = 0x00400000;
 
@@ -696,7 +551,8 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
 
     /**
      * Change type for {@link #TYPE_WINDOW_CONTENT_CHANGED} event:
-     * A node in the subtree rooted at the source node was added or removed.
+     * One or more content changes occurred in the the subtree rooted at the source node,
+     * or the subtree's structure changed when a node was added or removed.
      */
     public static final int CONTENT_CHANGE_TYPE_SUBTREE = 0x00000001;
 
@@ -712,6 +568,124 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
      */
     public static final int CONTENT_CHANGE_TYPE_CONTENT_DESCRIPTION = 0x00000004;
 
+    /**
+     * Change type for {@link #TYPE_WINDOW_STATE_CHANGED} event:
+     * The node's pane title changed.
+     */
+    public static final int CONTENT_CHANGE_TYPE_PANE_TITLE = 0x00000008;
+
+    /**
+     * Change type for {@link #TYPE_WINDOW_STATE_CHANGED} event:
+     * The node has a pane title, and either just appeared or just was assigned a title when it
+     * had none before.
+     */
+    public static final int CONTENT_CHANGE_TYPE_PANE_APPEARED = 0x00000010;
+
+    /**
+     * Change type for {@link #TYPE_WINDOW_STATE_CHANGED} event:
+     * Can mean one of two slightly different things. The primary meaning is that the node has
+     * a pane title, and was removed from the node hierarchy. It will also be sent if the pane
+     * title is set to {@code null} after it contained a title.
+     * No source will be returned if the node is no longer on the screen. To make the change more
+     * clear for the user, the first entry in {@link #getText()} will return the value that would
+     * have been returned by {@code getSource().getPaneTitle()}.
+     */
+    public static final int CONTENT_CHANGE_TYPE_PANE_DISAPPEARED = 0x00000020;
+
+    /**
+     * Change type for {@link #TYPE_WINDOWS_CHANGED} event:
+     * The window was added.
+     */
+    public static final int WINDOWS_CHANGE_ADDED = 0x00000001;
+
+    /**
+     * Change type for {@link #TYPE_WINDOWS_CHANGED} event:
+     * A window was removed.
+     */
+    public static final int WINDOWS_CHANGE_REMOVED = 0x00000002;
+
+    /**
+     * Change type for {@link #TYPE_WINDOWS_CHANGED} event:
+     * The window's title changed.
+     */
+    public static final int WINDOWS_CHANGE_TITLE = 0x00000004;
+
+    /**
+     * Change type for {@link #TYPE_WINDOWS_CHANGED} event:
+     * The window's bounds changed.
+     */
+    public static final int WINDOWS_CHANGE_BOUNDS = 0x00000008;
+
+    /**
+     * Change type for {@link #TYPE_WINDOWS_CHANGED} event:
+     * The window's layer changed.
+     */
+    public static final int WINDOWS_CHANGE_LAYER = 0x00000010;
+
+    /**
+     * Change type for {@link #TYPE_WINDOWS_CHANGED} event:
+     * The window's {@link AccessibilityWindowInfo#isActive()} changed.
+     */
+    public static final int WINDOWS_CHANGE_ACTIVE = 0x00000020;
+
+    /**
+     * Change type for {@link #TYPE_WINDOWS_CHANGED} event:
+     * The window's {@link AccessibilityWindowInfo#isFocused()} changed.
+     */
+    public static final int WINDOWS_CHANGE_FOCUSED = 0x00000040;
+
+    /**
+     * Change type for {@link #TYPE_WINDOWS_CHANGED} event:
+     * The window's {@link AccessibilityWindowInfo#isAccessibilityFocused()} changed.
+     */
+    public static final int WINDOWS_CHANGE_ACCESSIBILITY_FOCUSED = 0x00000080;
+
+    /**
+     * Change type for {@link #TYPE_WINDOWS_CHANGED} event:
+     * The window's parent changed.
+     */
+    public static final int WINDOWS_CHANGE_PARENT = 0x00000100;
+
+    /**
+     * Change type for {@link #TYPE_WINDOWS_CHANGED} event:
+     * The window's children changed.
+     */
+    public static final int WINDOWS_CHANGE_CHILDREN = 0x00000200;
+
+    /**
+     * Change type for {@link #TYPE_WINDOWS_CHANGED} event:
+     * The window either entered or exited picture-in-picture mode.
+     */
+    public static final int WINDOWS_CHANGE_PIP = 0x00000400;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(flag = true, prefix = { "WINDOWS_CHANGE_" }, value = {
+            WINDOWS_CHANGE_ADDED,
+            WINDOWS_CHANGE_REMOVED,
+            WINDOWS_CHANGE_TITLE,
+            WINDOWS_CHANGE_BOUNDS,
+            WINDOWS_CHANGE_LAYER,
+            WINDOWS_CHANGE_ACTIVE,
+            WINDOWS_CHANGE_FOCUSED,
+            WINDOWS_CHANGE_ACCESSIBILITY_FOCUSED,
+            WINDOWS_CHANGE_PARENT,
+            WINDOWS_CHANGE_CHILDREN,
+            WINDOWS_CHANGE_PIP
+    })
+    public @interface WindowsChangeTypes {}
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(flag = true, prefix = { "CONTENT_CHANGE_TYPE_" },
+            value = {
+                    CONTENT_CHANGE_TYPE_UNDEFINED,
+                    CONTENT_CHANGE_TYPE_SUBTREE,
+                    CONTENT_CHANGE_TYPE_TEXT,
+                    CONTENT_CHANGE_TYPE_CONTENT_DESCRIPTION,
+                    CONTENT_CHANGE_TYPE_PANE_TITLE
+            })
+    public @interface ContentChangeTypes {}
 
     /** @hide */
     @IntDef(flag = true, prefix = { "TYPE_" }, value = {
@@ -782,6 +756,7 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
     int mMovementGranularity;
     int mAction;
     int mContentChangeTypes;
+    int mWindowChangeTypes;
 
     private ArrayList<AccessibilityRecord> mRecords;
 
@@ -802,6 +777,7 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
         mMovementGranularity = event.mMovementGranularity;
         mAction = event.mAction;
         mContentChangeTypes = event.mContentChangeTypes;
+        mWindowChangeTypes = event.mWindowChangeTypes;
         mEventTime = event.mEventTime;
         mPackageName = event.mPackageName;
     }
@@ -885,6 +861,7 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
      *         <li>{@link AccessibilityEvent#CONTENT_CHANGE_TYPE_UNDEFINED}
      *         </ul>
      */
+    @ContentChangeTypes
     public int getContentChangeTypes() {
         return mContentChangeTypes;
     }
@@ -913,12 +890,49 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
      * @throws IllegalStateException If called from an AccessibilityService.
      * @see #getContentChangeTypes()
      */
-    public void setContentChangeTypes(int changeTypes) {
+    public void setContentChangeTypes(@ContentChangeTypes int changeTypes) {
         enforceNotSealed();
         mContentChangeTypes = changeTypes;
     }
 
     /**
+     * Get the bit mask of change types signaled by a {@link #TYPE_WINDOWS_CHANGED} event. A
+     * single event may represent multiple change types.
+     *
+     * @return The bit mask of change types.
+     */
+    @WindowsChangeTypes
+    public int getWindowChanges() {
+        return mWindowChangeTypes;
+    }
+
+    /** @hide  */
+    public void setWindowChanges(@WindowsChangeTypes int changes) {
+        mWindowChangeTypes = changes;
+    }
+
+    private static String windowChangeTypesToString(@WindowsChangeTypes int types) {
+        return BitUtils.flagsToString(types, AccessibilityEvent::singleWindowChangeTypeToString);
+    }
+
+    private static String singleWindowChangeTypeToString(int type) {
+        switch (type) {
+            case WINDOWS_CHANGE_ADDED: return "WINDOWS_CHANGE_ADDED";
+            case WINDOWS_CHANGE_REMOVED: return "WINDOWS_CHANGE_REMOVED";
+            case WINDOWS_CHANGE_TITLE: return "WINDOWS_CHANGE_TITLE";
+            case WINDOWS_CHANGE_BOUNDS: return "WINDOWS_CHANGE_BOUNDS";
+            case WINDOWS_CHANGE_LAYER: return "WINDOWS_CHANGE_LAYER";
+            case WINDOWS_CHANGE_ACTIVE: return "WINDOWS_CHANGE_ACTIVE";
+            case WINDOWS_CHANGE_FOCUSED: return "WINDOWS_CHANGE_FOCUSED";
+            case WINDOWS_CHANGE_ACCESSIBILITY_FOCUSED:
+                return "WINDOWS_CHANGE_ACCESSIBILITY_FOCUSED";
+            case WINDOWS_CHANGE_PARENT: return "WINDOWS_CHANGE_PARENT";
+            case WINDOWS_CHANGE_CHILDREN: return "WINDOWS_CHANGE_CHILDREN";
+            default: return Integer.toHexString(type);
+        }
+    }
+
+    /**
      * Sets the event type.
      *
      * @param eventType The event type.
@@ -1025,6 +1039,26 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
     }
 
     /**
+     * Convenience method to obtain a {@link #TYPE_WINDOWS_CHANGED} event for a specific window and
+     * change set.
+     *
+     * @param windowId The ID of the window that changed
+     * @param windowChangeTypes The changes to populate
+     * @return An instance of a TYPE_WINDOWS_CHANGED, populated with the requested fields and with
+     *         importantForAccessibility set to {@code true}.
+     *
+     * @hide
+     */
+    public static AccessibilityEvent obtainWindowsChangedEvent(
+            int windowId, int windowChangeTypes) {
+        final AccessibilityEvent event = AccessibilityEvent.obtain(TYPE_WINDOWS_CHANGED);
+        event.setWindowId(windowId);
+        event.setWindowChanges(windowChangeTypes);
+        event.setImportantForAccessibility(true);
+        return event;
+    }
+
+    /**
      * Returns a cached instance if such is available or a new one is
      * instantiated with its type property set.
      *
@@ -1099,6 +1133,7 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
         mMovementGranularity = 0;
         mAction = 0;
         mContentChangeTypes = 0;
+        mWindowChangeTypes = 0;
         mPackageName = null;
         mEventTime = 0;
         if (mRecords != null) {
@@ -1120,6 +1155,7 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
         mMovementGranularity = parcel.readInt();
         mAction = parcel.readInt();
         mContentChangeTypes = parcel.readInt();
+        mWindowChangeTypes = parcel.readInt();
         mPackageName = TextUtils.CHAR_SEQUENCE_CREATOR.createFromParcel(parcel);
         mEventTime = parcel.readLong();
         mConnectionId = parcel.readInt();
@@ -1178,6 +1214,7 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
         parcel.writeInt(mMovementGranularity);
         parcel.writeInt(mAction);
         parcel.writeInt(mContentChangeTypes);
+        parcel.writeInt(mWindowChangeTypes);
         TextUtils.writeToParcel(mPackageName, parcel, 0);
         parcel.writeLong(mEventTime);
         parcel.writeInt(mConnectionId);
@@ -1236,41 +1273,33 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
         builder.append("EventType: ").append(eventTypeToString(mEventType));
         builder.append("; EventTime: ").append(mEventTime);
         builder.append("; PackageName: ").append(mPackageName);
-        builder.append("; MovementGranularity: ").append(mMovementGranularity);
-        builder.append("; Action: ").append(mAction);
-        builder.append(super.toString());
-        if (DEBUG) {
-            builder.append("\n");
+        if (!DEBUG_CONCISE_TOSTRING || mMovementGranularity != 0) {
+            builder.append("; MovementGranularity: ").append(mMovementGranularity);
+        }
+        if (!DEBUG_CONCISE_TOSTRING || mAction != 0) {
+            builder.append("; Action: ").append(mAction);
+        }
+        if (!DEBUG_CONCISE_TOSTRING || mContentChangeTypes != 0) {
             builder.append("; ContentChangeTypes: ").append(
                     contentChangeTypesToString(mContentChangeTypes));
-            builder.append("; sourceWindowId: ").append(mSourceWindowId);
-            builder.append("; mSourceNodeId: ").append(mSourceNodeId);
-            for (int i = 0; i < getRecordCount(); i++) {
-                final AccessibilityRecord record = getRecord(i);
-                builder.append("  Record ");
-                builder.append(i);
-                builder.append(":");
-                builder.append(" [ ClassName: " + record.mClassName);
-                builder.append("; Text: " + record.mText);
-                builder.append("; ContentDescription: " + record.mContentDescription);
-                builder.append("; ItemCount: " + record.mItemCount);
-                builder.append("; CurrentItemIndex: " + record.mCurrentItemIndex);
-                builder.append("; IsEnabled: " + record.isEnabled());
-                builder.append("; IsPassword: " + record.isPassword());
-                builder.append("; IsChecked: " + record.isChecked());
-                builder.append("; IsFullScreen: " + record.isFullScreen());
-                builder.append("; Scrollable: " + record.isScrollable());
-                builder.append("; BeforeText: " + record.mBeforeText);
-                builder.append("; FromIndex: " + record.mFromIndex);
-                builder.append("; ToIndex: " + record.mToIndex);
-                builder.append("; ScrollX: " + record.mScrollX);
-                builder.append("; ScrollY: " + record.mScrollY);
-                builder.append("; AddedCount: " + record.mAddedCount);
-                builder.append("; RemovedCount: " + record.mRemovedCount);
-                builder.append("; ParcelableData: " + record.mParcelableData);
-                builder.append(" ]");
+        }
+        if (!DEBUG_CONCISE_TOSTRING || mWindowChangeTypes != 0) {
+            builder.append("; WindowChangeTypes: ").append(
+                    contentChangeTypesToString(mWindowChangeTypes));
+        }
+        super.appendTo(builder);
+        if (DEBUG || DEBUG_CONCISE_TOSTRING) {
+            if (!DEBUG_CONCISE_TOSTRING) {
                 builder.append("\n");
             }
+            if (DEBUG) {
+                builder.append("; SourceWindowId: ").append(mSourceWindowId);
+                builder.append("; SourceNodeId: ").append(mSourceNodeId);
+            }
+            for (int i = 0; i < getRecordCount(); i++) {
+                builder.append("  Record ").append(i).append(":");
+                getRecord(i).appendTo(builder).append("\n");
+            }
         } else {
             builder.append("; recordCount: ").append(getRecordCount());
         }
diff --git a/android/view/accessibility/AccessibilityNodeInfo.java b/android/view/accessibility/AccessibilityNodeInfo.java
index 28ef6978..23e7d619 100644
--- a/android/view/accessibility/AccessibilityNodeInfo.java
+++ b/android/view/accessibility/AccessibilityNodeInfo.java
@@ -639,6 +639,8 @@ public class AccessibilityNodeInfo implements Parcelable {
 
     private static final int BOOLEAN_PROPERTY_IS_SHOWING_HINT = 0x0100000;
 
+    private static final int BOOLEAN_PROPERTY_IS_HEADING = 0x0200000;
+
     /**
      * Bits that provide the id of a virtual descendant of a view.
      */
@@ -723,7 +725,9 @@ public class AccessibilityNodeInfo implements Parcelable {
     private CharSequence mText;
     private CharSequence mHintText;
     private CharSequence mError;
+    private CharSequence mPaneTitle;
     private CharSequence mContentDescription;
+    private CharSequence mTooltipText;
     private String mViewIdResourceName;
     private ArrayList<String> mExtraDataKeys;
 
@@ -2033,6 +2037,33 @@ public class AccessibilityNodeInfo implements Parcelable {
     }
 
     /**
+     * If this node represents a visually distinct region of the screen that may update separately
+     * from the rest of the window, it is considered a pane. Set the pane title to indicate that
+     * the node is a pane, and to provide a title for it.
+     * <p>
+     *   <strong>Note:</strong> Cannot be called from an
+     *   {@link android.accessibilityservice.AccessibilityService}.
+     *   This class is made immutable before being delivered to an AccessibilityService.
+     * </p>
+     * @param paneTitle The title of the pane represented by this node.
+     */
+    public void setPaneTitle(@Nullable CharSequence paneTitle) {
+        enforceNotSealed();
+        mPaneTitle = (paneTitle == null)
+                ? null : paneTitle.subSequence(0, paneTitle.length());
+    }
+
+    /**
+     * Get the title of the pane represented by this node.
+     *
+     * @return The title of the pane represented by this node, or {@code null} if this node does
+     *         not represent a pane.
+     */
+    public @Nullable CharSequence getPaneTitle() {
+        return mPaneTitle;
+    }
+
+    /**
      * Get the drawing order of the view corresponding it this node.
      * <p>
      * Drawing order is determined only within the node's parent, so this index is only relative
@@ -2381,6 +2412,30 @@ public class AccessibilityNodeInfo implements Parcelable {
     }
 
     /**
+     * Returns whether node represents a heading.
+     *
+     * @return {@code true} if the node is a heading, {@code false} otherwise.
+     */
+    public boolean isHeading() {
+        return getBooleanProperty(BOOLEAN_PROPERTY_IS_HEADING);
+    }
+
+    /**
+     * Sets whether the node represents a heading.
+     *
+     * <p>
+     *   <strong>Note:</strong> Cannot be called from an
+     *   {@link android.accessibilityservice.AccessibilityService}.
+     *   This class is made immutable before being delivered to an AccessibilityService.
+     * </p>
+     *
+     * @param isHeading {@code true} if the node is a heading, {@code false} otherwise.
+     */
+    public void setHeading(boolean isHeading) {
+        setBooleanProperty(BOOLEAN_PROPERTY_IS_HEADING, isHeading);
+    }
+
+    /**
      * Gets the package this node comes from.
      *
      * @return The package name.
@@ -2601,6 +2656,34 @@ public class AccessibilityNodeInfo implements Parcelable {
     }
 
     /**
+     * Gets the tooltip text of this node.
+     *
+     * @return The tooltip text.
+     */
+    @Nullable
+    public CharSequence getTooltipText() {
+        return mTooltipText;
+    }
+
+    /**
+     * Sets the tooltip text of this node.
+     * <p>
+     *   <strong>Note:</strong> Cannot be called from an
+     *   {@link android.accessibilityservice.AccessibilityService}.
+     *   This class is made immutable before being delivered to an AccessibilityService.
+     * </p>
+     *
+     * @param tooltipText The tooltip text.
+     *
+     * @throws IllegalStateException If called from an AccessibilityService.
+     */
+    public void setTooltipText(@Nullable CharSequence tooltipText) {
+        enforceNotSealed();
+        mTooltipText = (tooltipText == null) ? null
+                : tooltipText.subSequence(0, tooltipText.length());
+    }
+
+    /**
      * Sets the view for which the view represented by this info serves as a
      * label for accessibility purposes.
      *
@@ -3151,6 +3234,14 @@ public class AccessibilityNodeInfo implements Parcelable {
             nonDefaultFields |= bitAt(fieldIndex);
         }
         fieldIndex++;
+        if (!Objects.equals(mPaneTitle, DEFAULT.mPaneTitle)) {
+            nonDefaultFields |= bitAt(fieldIndex);
+        }
+        fieldIndex++;
+        if (!Objects.equals(mTooltipText, DEFAULT.mTooltipText)) {
+            nonDefaultFields |= bitAt(fieldIndex);
+        }
+        fieldIndex++;
         if (!Objects.equals(mViewIdResourceName, DEFAULT.mViewIdResourceName)) {
             nonDefaultFields |= bitAt(fieldIndex);
         }
@@ -3270,6 +3361,9 @@ public class AccessibilityNodeInfo implements Parcelable {
         if (isBitSet(nonDefaultFields, fieldIndex++)) {
             parcel.writeCharSequence(mContentDescription);
         }
+        if (isBitSet(nonDefaultFields, fieldIndex++)) parcel.writeCharSequence(mPaneTitle);
+        if (isBitSet(nonDefaultFields, fieldIndex++)) parcel.writeCharSequence(mTooltipText);
+
         if (isBitSet(nonDefaultFields, fieldIndex++)) parcel.writeString(mViewIdResourceName);
 
         if (isBitSet(nonDefaultFields, fieldIndex++)) parcel.writeInt(mTextSelectionStart);
@@ -3341,6 +3435,8 @@ public class AccessibilityNodeInfo implements Parcelable {
         mHintText = other.mHintText;
         mError = other.mError;
         mContentDescription = other.mContentDescription;
+        mPaneTitle = other.mPaneTitle;
+        mTooltipText = other.mTooltipText;
         mViewIdResourceName = other.mViewIdResourceName;
 
         if (mActions != null) mActions.clear();
@@ -3461,6 +3557,8 @@ public class AccessibilityNodeInfo implements Parcelable {
         if (isBitSet(nonDefaultFields, fieldIndex++)) {
             mContentDescription = parcel.readCharSequence();
         }
+        if (isBitSet(nonDefaultFields, fieldIndex++)) mPaneTitle = parcel.readString();
+        if (isBitSet(nonDefaultFields, fieldIndex++)) mTooltipText = parcel.readCharSequence();
         if (isBitSet(nonDefaultFields, fieldIndex++)) mViewIdResourceName = parcel.readString();
 
         if (isBitSet(nonDefaultFields, fieldIndex++)) mTextSelectionStart = parcel.readInt();
@@ -3623,6 +3721,10 @@ public class AccessibilityNodeInfo implements Parcelable {
                 return "ACTION_SET_PROGRESS";
             case R.id.accessibilityActionContextClick:
                 return "ACTION_CONTEXT_CLICK";
+            case R.id.accessibilityActionShowTooltip:
+                return "ACTION_SHOW_TOOLTIP";
+            case R.id.accessibilityActionHideTooltip:
+                return "ACTION_HIDE_TOOLTIP";
             default:
                 return "ACTION_UNKNOWN";
         }
@@ -3736,6 +3838,7 @@ public class AccessibilityNodeInfo implements Parcelable {
         builder.append("; error: ").append(mError);
         builder.append("; maxTextLength: ").append(mMaxTextLength);
         builder.append("; contentDescription: ").append(mContentDescription);
+        builder.append("; tooltipText: ").append(mTooltipText);
         builder.append("; viewIdResName: ").append(mViewIdResourceName);
 
         builder.append("; checkable: ").append(isCheckable());
@@ -4150,6 +4253,20 @@ public class AccessibilityNodeInfo implements Parcelable {
         public static final AccessibilityAction ACTION_MOVE_WINDOW =
                 new AccessibilityAction(R.id.accessibilityActionMoveWindow);
 
+        /**
+         * Action to show a tooltip. A node should expose this action only for views with tooltip
+         * text that but are not currently showing a tooltip.
+         */
+        public static final AccessibilityAction ACTION_SHOW_TOOLTIP =
+                new AccessibilityAction(R.id.accessibilityActionShowTooltip);
+
+        /**
+         * Action to hide a tooltip. A node should expose this action only for views that are
+         * currently showing a tooltip.
+         */
+        public static final AccessibilityAction ACTION_HIDE_TOOLTIP =
+                new AccessibilityAction(R.id.accessibilityActionHideTooltip);
+
         private final int mActionId;
         private final CharSequence mLabel;
 
@@ -4562,7 +4679,8 @@ public class AccessibilityNodeInfo implements Parcelable {
          * @param rowSpan The number of rows the item spans.
          * @param columnIndex The column index at which the item is located.
          * @param columnSpan The number of columns the item spans.
-         * @param heading Whether the item is a heading.
+         * @param heading Whether the item is a heading. (Prefer
+         *                {@link AccessibilityNodeInfo#setHeading(boolean)}).
          */
         public static CollectionItemInfo obtain(int rowIndex, int rowSpan,
                 int columnIndex, int columnSpan, boolean heading) {
@@ -4576,7 +4694,8 @@ public class AccessibilityNodeInfo implements Parcelable {
          * @param rowSpan The number of rows the item spans.
          * @param columnIndex The column index at which the item is located.
          * @param columnSpan The number of columns the item spans.
-         * @param heading Whether the item is a heading.
+         * @param heading Whether the item is a heading. (Prefer
+         *                {@link AccessibilityNodeInfo#setHeading(boolean)})
          * @param selected Whether the item is selected.
          */
         public static CollectionItemInfo obtain(int rowIndex, int rowSpan,
@@ -4663,6 +4782,7 @@ public class AccessibilityNodeInfo implements Parcelable {
          * heading, table header, etc.
          *
          * @return If the item is a heading.
+         * @deprecated Use {@link AccessibilityNodeInfo#isHeading()}
          */
         public boolean isHeading() {
             return mHeading;
diff --git a/android/view/accessibility/AccessibilityRecord.java b/android/view/accessibility/AccessibilityRecord.java
index fa505c97..0a709f8f 100644
--- a/android/view/accessibility/AccessibilityRecord.java
+++ b/android/view/accessibility/AccessibilityRecord.java
@@ -16,6 +16,8 @@
 
 package android.view.accessibility;
 
+import static com.android.internal.util.CollectionUtils.isEmpty;
+
 import android.annotation.Nullable;
 import android.os.Parcelable;
 import android.view.View;
@@ -55,6 +57,8 @@ import java.util.List;
  * @see AccessibilityNodeInfo
  */
 public class AccessibilityRecord {
+    /** @hide */
+    protected static final boolean DEBUG_CONCISE_TOSTRING = false;
 
     private static final int UNDEFINED = -1;
 
@@ -888,28 +892,69 @@ public class AccessibilityRecord {
 
     @Override
     public String toString() {
-        StringBuilder builder = new StringBuilder();
-        builder.append(" [ ClassName: " + mClassName);
-        builder.append("; Text: " + mText);
-        builder.append("; ContentDescription: " + mContentDescription);
-        builder.append("; ItemCount: " + mItemCount);
-        builder.append("; CurrentItemIndex: " + mCurrentItemIndex);
-        builder.append("; IsEnabled: " + getBooleanProperty(PROPERTY_ENABLED));
-        builder.append("; IsPassword: " + getBooleanProperty(PROPERTY_PASSWORD));
-        builder.append("; IsChecked: " + getBooleanProperty(PROPERTY_CHECKED));
-        builder.append("; IsFullScreen: " + getBooleanProperty(PROPERTY_FULL_SCREEN));
-        builder.append("; Scrollable: " + getBooleanProperty(PROPERTY_SCROLLABLE));
-        builder.append("; BeforeText: " + mBeforeText);
-        builder.append("; FromIndex: " + mFromIndex);
-        builder.append("; ToIndex: " + mToIndex);
-        builder.append("; ScrollX: " + mScrollX);
-        builder.append("; ScrollY: " + mScrollY);
-        builder.append("; MaxScrollX: " + mMaxScrollX);
-        builder.append("; MaxScrollY: " + mMaxScrollY);
-        builder.append("; AddedCount: " + mAddedCount);
-        builder.append("; RemovedCount: " + mRemovedCount);
-        builder.append("; ParcelableData: " + mParcelableData);
+        return appendTo(new StringBuilder()).toString();
+    }
+
+    StringBuilder appendTo(StringBuilder builder) {
+        builder.append(" [ ClassName: ").append(mClassName);
+        if (!DEBUG_CONCISE_TOSTRING || !isEmpty(mText)) {
+            appendPropName(builder, "Text").append(mText);
+        }
+        append(builder, "ContentDescription", mContentDescription);
+        append(builder, "ItemCount", mItemCount);
+        append(builder, "CurrentItemIndex", mCurrentItemIndex);
+
+        appendUnless(true, PROPERTY_ENABLED, builder);
+        appendUnless(false, PROPERTY_PASSWORD, builder);
+        appendUnless(false, PROPERTY_CHECKED, builder);
+        appendUnless(false, PROPERTY_FULL_SCREEN, builder);
+        appendUnless(false, PROPERTY_SCROLLABLE, builder);
+
+        append(builder, "BeforeText", mBeforeText);
+        append(builder, "FromIndex", mFromIndex);
+        append(builder, "ToIndex", mToIndex);
+        append(builder, "ScrollX", mScrollX);
+        append(builder, "ScrollY", mScrollY);
+        append(builder, "MaxScrollX", mMaxScrollX);
+        append(builder, "MaxScrollY", mMaxScrollY);
+        append(builder, "AddedCount", mAddedCount);
+        append(builder, "RemovedCount", mRemovedCount);
+        append(builder, "ParcelableData", mParcelableData);
         builder.append(" ]");
-        return builder.toString();
+        return builder;
+    }
+
+    private void appendUnless(boolean defValue, int prop, StringBuilder builder) {
+        boolean value = getBooleanProperty(prop);
+        if (DEBUG_CONCISE_TOSTRING && value == defValue) return;
+        appendPropName(builder, singleBooleanPropertyToString(prop))
+                .append(value);
+    }
+
+    private static String singleBooleanPropertyToString(int prop) {
+        switch (prop) {
+            case PROPERTY_CHECKED: return "Checked";
+            case PROPERTY_ENABLED: return "Enabled";
+            case PROPERTY_PASSWORD: return "Password";
+            case PROPERTY_FULL_SCREEN: return "FullScreen";
+            case PROPERTY_SCROLLABLE: return "Scrollable";
+            case PROPERTY_IMPORTANT_FOR_ACCESSIBILITY:
+                return "ImportantForAccessibility";
+            default: return Integer.toHexString(prop);
+        }
+    }
+
+    private void append(StringBuilder builder, String propName, int propValue) {
+        if (DEBUG_CONCISE_TOSTRING && propValue == UNDEFINED) return;
+        appendPropName(builder, propName).append(propValue);
+    }
+
+    private void append(StringBuilder builder, String propName, Object propValue) {
+        if (DEBUG_CONCISE_TOSTRING && propValue == null) return;
+        appendPropName(builder, propName).append(propValue);
+    }
+
+    private StringBuilder appendPropName(StringBuilder builder, String propName) {
+        return builder.append("; ").append(propName).append(": ");
     }
 }
diff --git a/android/view/accessibility/AccessibilityViewHierarchyState.java b/android/view/accessibility/AccessibilityViewHierarchyState.java
new file mode 100644
index 00000000..447fafaa
--- /dev/null
+++ b/android/view/accessibility/AccessibilityViewHierarchyState.java
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.view.accessibility;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+
+/**
+ * Accessibility-related state of a {@link android.view.ViewRootImpl}
+ *
+ * @hide
+ */
+public class AccessibilityViewHierarchyState {
+    private @Nullable SendViewScrolledAccessibilityEvent mSendViewScrolledAccessibilityEvent;
+    private @Nullable SendWindowContentChangedAccessibilityEvent
+            mSendWindowContentChangedAccessibilityEvent;
+
+    /**
+     * @return a {@link SendViewScrolledAccessibilityEvent}, creating one if needed
+     */
+    public @NonNull SendViewScrolledAccessibilityEvent getSendViewScrolledAccessibilityEvent() {
+        if (mSendViewScrolledAccessibilityEvent == null) {
+            mSendViewScrolledAccessibilityEvent = new SendViewScrolledAccessibilityEvent();
+        }
+        return mSendViewScrolledAccessibilityEvent;
+    }
+
+    public boolean isScrollEventSenderInitialized() {
+        return mSendViewScrolledAccessibilityEvent != null;
+    }
+
+    /**
+     * @return a {@link SendWindowContentChangedAccessibilityEvent}, creating one if needed
+     */
+    public @NonNull SendWindowContentChangedAccessibilityEvent
+            getSendWindowContentChangedAccessibilityEvent() {
+        if (mSendWindowContentChangedAccessibilityEvent == null) {
+            mSendWindowContentChangedAccessibilityEvent =
+                    new SendWindowContentChangedAccessibilityEvent();
+        }
+        return mSendWindowContentChangedAccessibilityEvent;
+    }
+
+    public boolean isWindowContentChangedEventSenderInitialized() {
+        return mSendWindowContentChangedAccessibilityEvent != null;
+    }
+}
diff --git a/android/view/accessibility/AccessibilityWindowInfo.java b/android/view/accessibility/AccessibilityWindowInfo.java
index ef1a3f3b..c1c9174c 100644
--- a/android/view/accessibility/AccessibilityWindowInfo.java
+++ b/android/view/accessibility/AccessibilityWindowInfo.java
@@ -21,9 +21,12 @@ import android.annotation.TestApi;
 import android.graphics.Rect;
 import android.os.Parcel;
 import android.os.Parcelable;
+import android.text.TextUtils;
 import android.util.LongArray;
 import android.util.Pools.SynchronizedPool;
+import android.view.accessibility.AccessibilityEvent.WindowsChangeTypes;
 
+import java.util.Objects;
 import java.util.concurrent.atomic.AtomicInteger;
 
 /**
@@ -575,7 +578,7 @@ public final class AccessibilityWindowInfo implements Parcelable {
         StringBuilder builder = new StringBuilder();
         builder.append("AccessibilityWindowInfo[");
         builder.append("title=").append(mTitle);
-        builder.append("id=").append(mId);
+        builder.append(", id=").append(mId);
         builder.append(", type=").append(typeToString(mType));
         builder.append(", layer=").append(mLayer);
         builder.append(", bounds=").append(mBoundsInScreen);
@@ -713,6 +716,60 @@ public final class AccessibilityWindowInfo implements Parcelable {
         return false;
     }
 
+    /**
+     * Reports how this window differs from a possibly different state of the same window. The
+     * argument must have the same id and type as neither of those properties may change.
+     *
+     * @param other The new state.
+     * @return A set of flags showing how the window has changes, or 0 if the two states are the
+     * same.
+     *
+     * @hide
+     */
+    @WindowsChangeTypes
+    public int differenceFrom(AccessibilityWindowInfo other) {
+        if (other.mId != mId) {
+            throw new IllegalArgumentException("Not same window.");
+        }
+        if (other.mType != mType) {
+            throw new IllegalArgumentException("Not same type.");
+        }
+        int changes = 0;
+        if (!TextUtils.equals(mTitle, other.mTitle)) {
+            changes |= AccessibilityEvent.WINDOWS_CHANGE_TITLE;
+        }
+
+        if (!mBoundsInScreen.equals(other.mBoundsInScreen)) {
+            changes |= AccessibilityEvent.WINDOWS_CHANGE_BOUNDS;
+        }
+        if (mLayer != other.mLayer) {
+            changes |= AccessibilityEvent.WINDOWS_CHANGE_LAYER;
+        }
+        if (getBooleanProperty(BOOLEAN_PROPERTY_ACTIVE)
+                != other.getBooleanProperty(BOOLEAN_PROPERTY_ACTIVE)) {
+            changes |= AccessibilityEvent.WINDOWS_CHANGE_ACTIVE;
+        }
+        if (getBooleanProperty(BOOLEAN_PROPERTY_FOCUSED)
+                != other.getBooleanProperty(BOOLEAN_PROPERTY_FOCUSED)) {
+            changes |= AccessibilityEvent.WINDOWS_CHANGE_FOCUSED;
+        }
+        if (getBooleanProperty(BOOLEAN_PROPERTY_ACCESSIBILITY_FOCUSED)
+                != other.getBooleanProperty(BOOLEAN_PROPERTY_ACCESSIBILITY_FOCUSED)) {
+            changes |= AccessibilityEvent.WINDOWS_CHANGE_ACCESSIBILITY_FOCUSED;
+        }
+        if (getBooleanProperty(BOOLEAN_PROPERTY_PICTURE_IN_PICTURE)
+                != other.getBooleanProperty(BOOLEAN_PROPERTY_PICTURE_IN_PICTURE)) {
+            changes |= AccessibilityEvent.WINDOWS_CHANGE_PIP;
+        }
+        if (mParentId != other.mParentId) {
+            changes |= AccessibilityEvent.WINDOWS_CHANGE_PARENT;
+        }
+        if (!Objects.equals(mChildIds, other.mChildIds)) {
+            changes |= AccessibilityEvent.WINDOWS_CHANGE_CHILDREN;
+        }
+        return changes;
+    }
+
     public static final Parcelable.Creator<AccessibilityWindowInfo> CREATOR =
             new Creator<AccessibilityWindowInfo>() {
         @Override
diff --git a/android/view/accessibility/SendViewScrolledAccessibilityEvent.java b/android/view/accessibility/SendViewScrolledAccessibilityEvent.java
new file mode 100644
index 00000000..40a1b6a2
--- /dev/null
+++ b/android/view/accessibility/SendViewScrolledAccessibilityEvent.java
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.view.accessibility;
+
+
+import android.annotation.NonNull;
+import android.view.View;
+
+/**
+ * Sender for {@link AccessibilityEvent#TYPE_VIEW_SCROLLED} accessibility event.
+ *
+ * @hide
+ */
+public class SendViewScrolledAccessibilityEvent extends ThrottlingAccessibilityEventSender {
+
+    public int mDeltaX;
+    public int mDeltaY;
+
+    /**
+     * Post a scroll event to be sent for the given view
+     */
+    public void post(View source, int dx, int dy) {
+        if (!isPendingFor(source)) sendNowIfPending();
+
+        mDeltaX += dx;
+        mDeltaY += dy;
+
+        if (!isPendingFor(source)) scheduleFor(source);
+    }
+
+    @Override
+    protected void performSendEvent(@NonNull View source) {
+        AccessibilityEvent event = AccessibilityEvent.obtain(AccessibilityEvent.TYPE_VIEW_SCROLLED);
+        event.setScrollDeltaX(mDeltaX);
+        event.setScrollDeltaY(mDeltaY);
+        source.sendAccessibilityEventUnchecked(event);
+    }
+
+    @Override
+    protected void resetState(@NonNull View source) {
+        mDeltaX = 0;
+        mDeltaY = 0;
+    }
+}
diff --git a/android/view/accessibility/SendWindowContentChangedAccessibilityEvent.java b/android/view/accessibility/SendWindowContentChangedAccessibilityEvent.java
new file mode 100644
index 00000000..df38fba5
--- /dev/null
+++ b/android/view/accessibility/SendWindowContentChangedAccessibilityEvent.java
@@ -0,0 +1,111 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.view.accessibility;
+
+
+import static com.android.internal.util.ObjectUtils.firstNotNull;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.view.View;
+import android.view.ViewParent;
+
+import java.util.HashSet;
+
+/**
+ * @hide
+ */
+public class SendWindowContentChangedAccessibilityEvent
+        extends ThrottlingAccessibilityEventSender {
+
+    private int mChangeTypes = 0;
+
+    private HashSet<View> mTempHashSet;
+
+    @Override
+    protected void performSendEvent(@NonNull View source) {
+        AccessibilityEvent event = AccessibilityEvent.obtain();
+        event.setEventType(AccessibilityEvent.TYPE_WINDOW_CONTENT_CHANGED);
+        event.setContentChangeTypes(mChangeTypes);
+        source.sendAccessibilityEventUnchecked(event);
+    }
+
+    @Override
+    protected void resetState(@Nullable View source) {
+        if (source != null) {
+            source.resetSubtreeAccessibilityStateChanged();
+        }
+        mChangeTypes = 0;
+    }
+
+    /**
+     * Post the {@link AccessibilityEvent#TYPE_WINDOW_CONTENT_CHANGED} event with the given
+     * {@link AccessibilityEvent#getContentChangeTypes change type} for the given view
+     */
+    public void runOrPost(View source, int changeType) {
+        if (source.getAccessibilityLiveRegion() != View.ACCESSIBILITY_LIVE_REGION_NONE) {
+            sendNowIfPending();
+            mChangeTypes = changeType;
+            sendNow(source);
+        } else {
+            mChangeTypes |= changeType;
+            scheduleFor(source);
+        }
+    }
+
+    @Override
+    protected @Nullable View tryMerge(@NonNull View oldSource, @NonNull View newSource) {
+        // If there is no common predecessor, then oldSource points to
+        // a removed view, hence in this case always prefer the newSource.
+        return firstNotNull(
+                getCommonPredecessor(oldSource, newSource),
+                newSource);
+    }
+
+    private View getCommonPredecessor(View first, View second) {
+        if (mTempHashSet == null) {
+            mTempHashSet = new HashSet<>();
+        }
+        HashSet<View> seen = mTempHashSet;
+        seen.clear();
+        View firstCurrent = first;
+        while (firstCurrent != null) {
+            seen.add(firstCurrent);
+            ViewParent firstCurrentParent = firstCurrent.getParent();
+            if (firstCurrentParent instanceof View) {
+                firstCurrent = (View) firstCurrentParent;
+            } else {
+                firstCurrent = null;
+            }
+        }
+        View secondCurrent = second;
+        while (secondCurrent != null) {
+            if (seen.contains(secondCurrent)) {
+                seen.clear();
+                return secondCurrent;
+            }
+            ViewParent secondCurrentParent = secondCurrent.getParent();
+            if (secondCurrentParent instanceof View) {
+                secondCurrent = (View) secondCurrentParent;
+            } else {
+                secondCurrent = null;
+            }
+        }
+        seen.clear();
+        return null;
+    }
+}
diff --git a/android/view/accessibility/ThrottlingAccessibilityEventSender.java b/android/view/accessibility/ThrottlingAccessibilityEventSender.java
new file mode 100644
index 00000000..66fa3010
--- /dev/null
+++ b/android/view/accessibility/ThrottlingAccessibilityEventSender.java
@@ -0,0 +1,248 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.view.accessibility;
+
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.os.Handler;
+import android.os.Looper;
+import android.os.SystemClock;
+import android.util.Log;
+import android.view.View;
+import android.view.ViewConfiguration;
+import android.view.ViewRootImpl;
+import android.view.ViewRootImpl.CalledFromWrongThreadException;
+
+/**
+ * A throttling {@link AccessibilityEvent} sender that relies on its currently associated
+ * 'source' view's {@link View#postDelayed delayed execution} to delay and possibly
+ * {@link #tryMerge merge} together any events that come in less than
+ * {@link ViewConfiguration#getSendRecurringAccessibilityEventsInterval
+ * the configured amount of milliseconds} apart.
+ *
+ * The suggested usage is to create a singleton extending this class, holding any state specific to
+ * the particular event type that the subclass represents, and have an 'entrypoint' method that
+ * delegates to {@link #scheduleFor(View)}.
+ * For example:
+ *
+ * {@code
+ *     public void post(View view, String text, int resId) {
+ *         mText = text;
+ *         mId = resId;
+ *         scheduleFor(view);
+ *     }
+ * }
+ *
+ * @see #scheduleFor(View)
+ * @see #tryMerge(View, View)
+ * @see #performSendEvent(View)
+ * @hide
+ */
+public abstract class ThrottlingAccessibilityEventSender {
+
+    private static final boolean DEBUG = false;
+    private static final String LOG_TAG = "ThrottlingA11ySender";
+
+    View mSource;
+    private long mLastSendTimeMillis = Long.MIN_VALUE;
+    private boolean mIsPending = false;
+
+    private final Runnable mWorker = () -> {
+        View source = mSource;
+        if (DEBUG) Log.d(LOG_TAG, thisClass() + ".run(mSource = " + source + ")");
+
+        if (!checkAndResetIsPending() || source == null) {
+            resetStateInternal();
+            return;
+        }
+
+        // Accessibility may be turned off while we were waiting
+        if (isAccessibilityEnabled(source)) {
+            mLastSendTimeMillis = SystemClock.uptimeMillis();
+            performSendEvent(source);
+        }
+        resetStateInternal();
+    };
+
+    /**
+     * Populate and send an {@link AccessibilityEvent} using the given {@code source} view, as well
+     * as any extra data from this instance's state.
+     *
+     * Send the event via {@link View#sendAccessibilityEventUnchecked(AccessibilityEvent)} or
+     * {@link View#sendAccessibilityEvent(int)} on the provided {@code source} view to allow for
+     * overrides of those methods on {@link View} subclasses to take effect, and/or make sure that
+     * an {@link View#getAccessibilityDelegate() accessibility delegate} is not ignored if any.
+     */
+    protected abstract void performSendEvent(@NonNull View source);
+
+    /**
+     * Perform optional cleanup after {@link #performSendEvent}
+     *
+     * @param source the view this event was associated with
+     */
+    protected abstract void resetState(@Nullable View source);
+
+    /**
+     * Attempt to merge the pending events for source views {@code oldSource} and {@code newSource}
+     * into one, with source set to the resulting {@link View}
+     *
+     * A result of {@code null} means merger is not possible, resulting in the currently pending
+     * event being flushed before proceeding.
+     */
+    protected @Nullable View tryMerge(@NonNull View oldSource, @NonNull View newSource) {
+        return null;
+    }
+
+    /**
+     * Schedules a {@link #performSendEvent} with the source {@link View} set to given
+     * {@code source}
+     *
+     * If an event is already scheduled a {@link #tryMerge merge} will be attempted.
+     * If merging is not possible (as indicated by the null result from {@link #tryMerge}),
+     * the currently scheduled event will be {@link #sendNow sent immediately} and the new one
+     * will be scheduled afterwards.
+     */
+    protected final void scheduleFor(@NonNull View source) {
+        if (DEBUG) Log.d(LOG_TAG, thisClass() + ".scheduleFor(source = " + source + ")");
+
+        Handler uiHandler = source.getHandler();
+        if (uiHandler == null || uiHandler.getLooper() != Looper.myLooper()) {
+            CalledFromWrongThreadException e = new CalledFromWrongThreadException(
+                    "Expected to be called from main thread but was called from "
+                            + Thread.currentThread());
+            // TODO: Throw the exception
+            Log.e(LOG_TAG, "Accessibility content change on non-UI thread. Future Android "
+                    + "versions will throw an exception.", e);
+        }
+
+        if (!isAccessibilityEnabled(source)) return;
+
+        if (mIsPending) {
+            View merged = tryMerge(mSource, source);
+            if (merged != null) {
+                setSource(merged);
+                return;
+            } else {
+                sendNow();
+            }
+        }
+
+        setSource(source);
+
+        final long timeSinceLastMillis = SystemClock.uptimeMillis() - mLastSendTimeMillis;
+        final long minEventIntervalMillis =
+                ViewConfiguration.getSendRecurringAccessibilityEventsInterval();
+        if (timeSinceLastMillis >= minEventIntervalMillis) {
+            sendNow();
+        } else {
+            mSource.postDelayed(mWorker, minEventIntervalMillis - timeSinceLastMillis);
+        }
+    }
+
+    static boolean isAccessibilityEnabled(@NonNull View contextProvider) {
+        return AccessibilityManager.getInstance(contextProvider.getContext()).isEnabled();
+    }
+
+    protected final void sendNow(View source) {
+        setSource(source);
+        sendNow();
+    }
+
+    private void sendNow() {
+        mSource.removeCallbacks(mWorker);
+        mWorker.run();
+    }
+
+    /**
+     * Flush the event if one is pending
+     */
+    public void sendNowIfPending() {
+        if (mIsPending) sendNow();
+    }
+
+    /**
+     * Cancel the event if one is pending and is for the given view
+     */
+    public final void cancelIfPendingFor(@NonNull View source) {
+        if (isPendingFor(source)) cancelIfPending(this);
+    }
+
+    /**
+     * @return whether an event is currently pending for the given source view
+     */
+    protected final boolean isPendingFor(@Nullable View source) {
+        return mIsPending && mSource == source;
+    }
+
+    /**
+     * Cancel the event if one is not null and pending
+     */
+    public static void cancelIfPending(@Nullable ThrottlingAccessibilityEventSender sender) {
+        if (sender == null || !sender.checkAndResetIsPending()) return;
+        sender.mSource.removeCallbacks(sender.mWorker);
+        sender.resetStateInternal();
+    }
+
+    void resetStateInternal() {
+        if (DEBUG) Log.d(LOG_TAG, thisClass() + ".resetStateInternal()");
+
+        resetState(mSource);
+        setSource(null);
+    }
+
+    boolean checkAndResetIsPending() {
+        if (mIsPending) {
+            mIsPending = false;
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    private void setSource(@Nullable View source) {
+        if (DEBUG) Log.d(LOG_TAG, thisClass() + ".setSource(" + source + ")");
+
+        if (source == null && mIsPending) {
+            Log.e(LOG_TAG, "mSource nullified while callback still pending: " + this);
+            return;
+        }
+
+        if (source != null && !mIsPending) {
+            // At most one can be pending at any given time
+            View oldSource = mSource;
+            if (oldSource != null) {
+                ViewRootImpl viewRootImpl = oldSource.getViewRootImpl();
+                if (viewRootImpl != null) {
+                    viewRootImpl.flushPendingAccessibilityEvents();
+                }
+            }
+            mIsPending = true;
+        }
+        mSource = source;
+    }
+
+    String thisClass() {
+        return getClass().getSimpleName();
+    }
+
+    @Override
+    public String toString() {
+        return thisClass() + "(" + mSource + ")";
+    }
+
+}