Introduces Android API level linting, fixes all current API lint errors.

This CL attempts to annotate accesses on >16 API levels using as
small scopes as possible. The TargetApi notations mean "yes, I know
I'm accessing a higher API and I take responsibility for gating the
call on Android API level". The Encoder/Decoder classes are annotated
on the whole class, but they're only accessed through JNI; we should
annotate on method level otherwise and preferably on private methods.

This patch also fixes some compiler-level deprecation warnings (i.e.
-Xlint:deprecation), but probably not all of them.

BUG=webrtc:5063
R=henrika@webrtc.org, kjellander@webrtc.org, magjed@webrtc.org

Review URL: https://codereview.webrtc.org/1412673008 .

Cr-Commit-Position: refs/heads/master@{#10624}

4 files changed, 49 insertions, 18 deletions

diff --git a/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioEffects.java b/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioEffects.java
index 7cd769a63c..c3ab043868 100644
--- a/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioEffects.java
+++ b/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioEffects.java
@@ -10,6 +10,7 @@
 
 package org.webrtc.voiceengine;
 
+import android.annotation.TargetApi;
 import android.media.audiofx.AcousticEchoCanceler;
 import android.media.audiofx.AudioEffect;
 import android.media.audiofx.AudioEffect.Descriptor;
@@ -119,6 +120,7 @@ class WebRtcAudioEffects {
 
   // Returns true if the platform AEC should be excluded based on its UUID.
   // AudioEffect.queryEffects() can throw IllegalStateException.
+  @TargetApi(18)
   private static boolean isAcousticEchoCancelerExcludedByUUID() {
     for (Descriptor d : AudioEffect.queryEffects()) {
       if (d.type.equals(AudioEffect.EFFECT_TYPE_AEC) &&
@@ -131,6 +133,7 @@ class WebRtcAudioEffects {
 
   // Returns true if the platform AGC should be excluded based on its UUID.
   // AudioEffect.queryEffects() can throw IllegalStateException.
+  @TargetApi(18)
   private static boolean isAutomaticGainControlExcludedByUUID() {
     for (Descriptor d : AudioEffect.queryEffects()) {
       if (d.type.equals(AudioEffect.EFFECT_TYPE_AGC) &&
@@ -143,6 +146,7 @@ class WebRtcAudioEffects {
 
   // Returns true if the platform NS should be excluded based on its UUID.
   // AudioEffect.queryEffects() can throw IllegalStateException.
+  @TargetApi(18)
   private static boolean isNoiseSuppressorExcludedByUUID() {
     for (Descriptor d : AudioEffect.queryEffects()) {
       if (d.type.equals(AudioEffect.EFFECT_TYPE_NS) &&
@@ -368,7 +372,11 @@ class WebRtcAudioEffects {
   // AudioEffect.Descriptor array that are actually not available on the device.
   // As an example: Samsung Galaxy S6 includes an AGC in the descriptor but
   // AutomaticGainControl.isAvailable() returns false.
+  @TargetApi(18)
   private boolean effectTypeIsVoIP(UUID type) {
+    if (!WebRtcAudioUtils.runningOnJellyBeanMR2OrHigher())
+      return false;
+
     return (AudioEffect.EFFECT_TYPE_AEC.equals(type)
         && isAcousticEchoCancelerSupported())
         || (AudioEffect.EFFECT_TYPE_AGC.equals(type)
diff --git a/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioManager.java b/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioManager.java
index 7359486a3f..f40317b25d 100644
--- a/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioManager.java
+++ b/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioManager.java
@@ -10,6 +10,7 @@
 
 package org.webrtc.voiceengine;
 
+import android.annotation.TargetApi;
 import android.content.Context;
 import android.content.pm.PackageManager;
 import android.media.AudioFormat;
@@ -189,20 +190,26 @@ public class WebRtcAudioManager {
     // No overrides available. Deliver best possible estimate based on default
     // Android AudioManager APIs.
     final int sampleRateHz;
-    if (!WebRtcAudioUtils.runningOnJellyBeanMR1OrHigher()) {
-      sampleRateHz = WebRtcAudioUtils.getDefaultSampleRateHz();
+    if (WebRtcAudioUtils.runningOnJellyBeanMR1OrHigher()) {
+      sampleRateHz = getSampleRateOnJellyBeanMR10OrHigher();
     } else {
-      String sampleRateString = audioManager.getProperty(
-          AudioManager.PROPERTY_OUTPUT_SAMPLE_RATE);
-      sampleRateHz = (sampleRateString == null)
-          ? WebRtcAudioUtils.getDefaultSampleRateHz()
-          : Integer.parseInt(sampleRateString);
+      sampleRateHz = WebRtcAudioUtils.getDefaultSampleRateHz();
     }
     Logging.d(TAG, "Sample rate is set to " + sampleRateHz + " Hz");
     return sampleRateHz;
   }
 
+  @TargetApi(17)
+  private int getSampleRateOnJellyBeanMR10OrHigher() {
+    String sampleRateString = audioManager.getProperty(
+        AudioManager.PROPERTY_OUTPUT_SAMPLE_RATE);
+    return (sampleRateString == null)
+        ? WebRtcAudioUtils.getDefaultSampleRateHz()
+        : Integer.parseInt(sampleRateString);
+  }
+
   // Returns the native output buffer size for low-latency output streams.
+  @TargetApi(17)
   private int getLowLatencyOutputFramesPerBuffer() {
     assertTrue(isLowLatencyOutputSupported());
     if (!WebRtcAudioUtils.runningOnJellyBeanMR1OrHigher()) {
diff --git a/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java b/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java
index 0602e44c23..11eb51383d 100644
--- a/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java
+++ b/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java
@@ -13,6 +13,7 @@ package org.webrtc.voiceengine;
 import java.lang.Thread;
 import java.nio.ByteBuffer;
 
+import android.annotation.TargetApi;
 import android.content.Context;
 import android.media.AudioFormat;
 import android.media.AudioManager;
@@ -90,13 +91,9 @@ class WebRtcAudioTrack {
         assertTrue(sizeInBytes <= byteBuffer.remaining());
         int bytesWritten = 0;
         if (WebRtcAudioUtils.runningOnLollipopOrHigher()) {
-          bytesWritten = audioTrack.write(byteBuffer,
-                                          sizeInBytes,
-                                          AudioTrack.WRITE_BLOCKING);
+          bytesWritten = writeOnLollipop(audioTrack, byteBuffer, sizeInBytes);
         } else {
-          bytesWritten = audioTrack.write(byteBuffer.array(),
-                                          byteBuffer.arrayOffset(),
-                                          sizeInBytes);
+          bytesWritten = writePreLollipop(audioTrack, byteBuffer, sizeInBytes);
         }
         if (bytesWritten != sizeInBytes) {
           Logging.e(TAG, "AudioTrack.write failed: " + bytesWritten);
@@ -123,6 +120,15 @@ class WebRtcAudioTrack {
       audioTrack.flush();
     }
 
+    @TargetApi(21)
+    private int writeOnLollipop(AudioTrack audioTrack, ByteBuffer byteBuffer, int sizeInBytes) {
+      return audioTrack.write(byteBuffer, sizeInBytes, AudioTrack.WRITE_BLOCKING);
+    }
+
+    private int writePreLollipop(AudioTrack audioTrack, ByteBuffer byteBuffer, int sizeInBytes) {
+      return audioTrack.write(byteBuffer.array(), byteBuffer.arrayOffset(), sizeInBytes);
+    }
+
     public void joinThread() {
       keepAlive = false;
       while (isAlive()) {
@@ -224,16 +230,21 @@ class WebRtcAudioTrack {
   private boolean setStreamVolume(int volume) {
     Logging.d(TAG, "setStreamVolume(" + volume + ")");
     assertTrue(audioManager != null);
-    if (WebRtcAudioUtils.runningOnLollipopOrHigher()) {
-      if (audioManager.isVolumeFixed()) {
-        Logging.e(TAG, "The device implements a fixed volume policy.");
-        return false;
-      }
+    if (isVolumeFixed()) {
+      Logging.e(TAG, "The device implements a fixed volume policy.");
+      return false;
     }
     audioManager.setStreamVolume(AudioManager.STREAM_VOICE_CALL, volume, 0);
     return true;
   }
 
+  @TargetApi(21)
+  private boolean isVolumeFixed() {
+    if (!WebRtcAudioUtils.runningOnLollipopOrHigher())
+      return false;
+    return audioManager.isVolumeFixed();
+  }
+
   /** Get current volume level for a phone call audio stream. */
   private int getStreamVolume() {
     Logging.d(TAG, "getStreamVolume");
diff --git a/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioUtils.java b/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioUtils.java
index 9d7a600190..45f564a4dd 100644
--- a/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioUtils.java
+++ b/webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioUtils.java
@@ -144,6 +144,11 @@ public final class WebRtcAudioUtils {
     return Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1;
   }
 
+  public static boolean runningOnJellyBeanMR2OrHigher() {
+    // July 24, 2013: Android 4.3. API Level 18.
+    return Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2;
+  }
+
   public static boolean runningOnLollipopOrHigher() {
     // API Level 21.
     return Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP;