Cherry-pick "[Android WebView] Provide user-initiated provisional load detection"webview-m40_r4ub-webview-m40-release

Original CL:
    https://crrev.com/7a3234c9a19a38726a4a984ff12e2b406423c1d3

Original description:
    [Android WebView] Provide user-initiated provisional load detection

    Do not synthesize page loading events on DOM modification, if the provisional
    load has been started from the API side.

    It appears that a lot of apps tend to use the following scenario:

    webView.loadUrl(...);
    webView.loadUrl('javascript:...');

    Which was triggering page loading events to be emitted. This scenario is
    dubious, as no one guarantees that loading will actually finish prior to
    executing javascript. But for compatibility reasons we must take it into
    account and not emit page loading events for "about:blank", as it seems
    that some apps do unexpected things when they receive it.

    BUG=458569,469099

Note that this patch also contains bits from this commit required for changes
in AwWebContentsObserver to work:
    https://crrev.com/5668d12d29ab659ad01dc0e0ffdf24f2eb5f187a

Bug: 19729876
Change-Id: I12c9610a13a382d725cc9a14fcb9879c92f1f461

1 files changed, 20 insertions, 5 deletions

diff --git a/android_webview/java/src/org/chromium/android_webview/AwWebContentsObserver.java b/android_webview/java/src/org/chromium/android_webview/AwWebContentsObserver.java
index cd45eadac2..bf012805bc 100644
--- a/android_webview/java/src/org/chromium/android_webview/AwWebContentsObserver.java
+++ b/android_webview/java/src/org/chromium/android_webview/AwWebContentsObserver.java
@@ -5,23 +5,30 @@
 package org.chromium.android_webview;
 
 import org.chromium.content.browser.WebContentsObserver;
+import org.chromium.content_public.browser.NavigationEntry;
 import org.chromium.content_public.browser.WebContents;
 import org.chromium.net.NetError;
+import org.chromium.ui.base.PageTransition;
+
+import java.lang.ref.WeakReference;
 
 /**
  * Routes notifications from WebContents to AwContentsClient and other listeners.
  */
 public class AwWebContentsObserver extends WebContentsObserver {
+    private final WeakReference<AwContents> mAwContents;
     private final AwContentsClient mAwContentsClient;
-    private boolean mHasStartedAnyProvisionalLoad = false;
+    private boolean mStartedNonApiProvisionalLoadInMainFrame = false;
 
-    public AwWebContentsObserver(WebContents webContents, AwContentsClient awContentsClient) {
+    public AwWebContentsObserver(
+            WebContents webContents, AwContents awContents,  AwContentsClient awContentsClient) {
         super(webContents);
+        mAwContents = new WeakReference<AwContents>(awContents);
         mAwContentsClient = awContentsClient;
     }
 
-    boolean hasStartedAnyProvisionalLoad() {
-        return mHasStartedAnyProvisionalLoad;
+    boolean hasStartedNonApiProvisionalLoadInMainFrame() {
+        return mStartedNonApiProvisionalLoadInMainFrame;
     }
 
     @Override
@@ -81,6 +88,14 @@ public class AwWebContentsObserver extends WebContentsObserver {
             String validatedUrl,
             boolean isErrorPage,
             boolean isIframeSrcdoc) {
-        mHasStartedAnyProvisionalLoad = true;
+        if (!isMainFrame) return;
+        AwContents awContents = mAwContents.get();
+        if (awContents != null) {
+            NavigationEntry pendingEntry = awContents.getNavigationController().getPendingEntry();
+            if (pendingEntry != null
+                    && (pendingEntry.getTransition() & PageTransition.FROM_API) == 0) {
+                mStartedNonApiProvisionalLoadInMainFrame = true;
+            }
+        }
     }
 }