Enable platform echo cancellation through the AudioRecord path.

media/base/android/java/src/org/chromium/media/AudioRecordInput.java

Index: media/base/android/java/src/org/chromium/media/AudioRecordInput.java
diff --git a/media/base/android/java/src/org/chromium/media/AudioRecordInput.java b/media/base/android/java/src/org/chromium/media/AudioRecordInput.java
index 0752731f80200d6a13f1d0124da84a81d3d9e2ec..b476009aab55b577a21bbdb2b8a9be0676240072 100644
--- a/media/base/android/java/src/org/chromium/media/AudioRecordInput.java
+++ b/media/base/android/java/src/org/chromium/media/AudioRecordInput.java
@@ -5,6 +5,9 @@
 package org.chromium.media;
 
 import android.content.Context;
+import android.media.audiofx.AcousticEchoCanceler;
+import android.media.audiofx.AudioEffect;
+import android.media.audiofx.AudioEffect.Descriptor;
 import android.media.AudioFormat;
 import android.media.AudioRecord;
 import android.media.MediaRecorder.AudioSource;
@@ -14,6 +17,7 @@ import java.nio.ByteBuffer;
 
 import org.chromium.base.CalledByNative;
 import org.chromium.base.JNINamespace;
+import org.chromium.media.AudioManagerAndroid;
 
 // Owned by its native counterpart declared in audio_record_input.h. Refer to
 // that class for general comments.
@@ -30,9 +34,11 @@ class AudioRecordInput {
     private final int mChannels;
     private final int mBitsPerSample;
     private final int mHardwareDelayBytes;
+    private final boolean mUsePlatformAEC;
     private ByteBuffer mBuffer;
     private AudioRecord mAudioRecord;
     private AudioRecordThread mAudioRecordThread;
+    private AcousticEchoCanceler mAEC;
 
     private class AudioRecordThread extends Thread {
         // The "volatile" synchronization technique is discussed here:
@@ -88,18 +94,20 @@ class AudioRecordInput {
 
     @CalledByNative
     private static AudioRecordInput createAudioRecordInput(long nativeAudioRecordInputStream,
-            int sampleRate, int channels, int bitsPerSample, int bytesPerBuffer) {
+            int sampleRate, int channels, int bitsPerSample, int bytesPerBuffer,
+            boolean usePlatformAEC) {
         return new AudioRecordInput(nativeAudioRecordInputStream, sampleRate, channels,
-                                    bitsPerSample, bytesPerBuffer);
+                                    bitsPerSample, bytesPerBuffer, usePlatformAEC);
     }
 
     private AudioRecordInput(long nativeAudioRecordInputStream, int sampleRate, int channels,
-                             int bitsPerSample, int bytesPerBuffer) {
+                             int bitsPerSample, int bytesPerBuffer, boolean usePlatformAEC) {
         mNativeAudioRecordInputStream = nativeAudioRecordInputStream;
         mSampleRate = sampleRate;
         mChannels = channels;
         mBitsPerSample = bitsPerSample;
         mHardwareDelayBytes = HARDWARE_DELAY_MS * sampleRate / 1000 * bitsPerSample / 8;
+        mUsePlatformAEC = usePlatformAEC;
 
         // We use a direct buffer so that the native class can have access to
         // the underlying memory address. This avoids the need to copy from a
@@ -170,6 +178,35 @@ class AudioRecordInput {
             return false;
         }
 
+        // Only try to modify the platform AEC state if it's supported.
+        if (AudioManagerAndroid.isPlatformAECSupported()) {
+            mAEC = AcousticEchoCanceler.create(mAudioRecord.getAudioSessionId());
+            if (mAEC == null) {
+                Log.wtf(TAG, "AcousticEchoCanceler.create failed");
+                return false;
+            }
+            try {
+                Descriptor descriptor = mAEC.getDescriptor();
+                Log.d(TAG, "AcousticEchoCanceler " +
+                        "name: " + descriptor.name + ", " +
+                        "implementor: " + descriptor.implementor + ", " +
+                        "uuid: " + descriptor.uuid);
+            } catch (IllegalStateException e) {
+                Log.w(TAG, "getDescriptor failed", e);
+                // Not fatal.
+            }
+            try {
+                int ret = mAEC.setEnabled(mUsePlatformAEC);
+                if (ret != AudioEffect.SUCCESS) {
+                    Log.wtf(TAG, "setEnabled error: " + ret);
+                    return false;
+                }
+            } catch (IllegalStateException e) {
+                Log.wtf(TAG, "setEnabled failed", e);
+                return false;
+            }
+            Log.d(TAG, "AcousticEchoCanceler.setEnabled(" + mUsePlatformAEC + ")");
+        }
         return true;
     }
 
@@ -209,6 +246,11 @@ class AudioRecordInput {
         }
         mAudioRecord.release();
         mAudioRecord = null;
+
+        if (mAEC != null) {
+            mAEC.release();
+            mAEC = null;
+        }
     }
 
     private native void nativeCacheDirectBufferAddress(long nativeAudioRecordInputStream,