Enable platform echo cancellation through the AudioRecord path.

media/audio/android/audio_manager_android.cc

Index: media/audio/android/audio_manager_android.cc
diff --git a/media/audio/android/audio_manager_android.cc b/media/audio/android/audio_manager_android.cc
index b588768bbd08c1fcfbb75df70248a9da752a28a4..75840052f3c3bbc4fef2ada009dd8adf2b0c9cc7 100644
--- a/media/audio/android/audio_manager_android.cc
+++ b/media/audio/android/audio_manager_android.cc
@@ -11,6 +11,7 @@
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "jni/AudioManagerAndroid_jni.h"
+#include "media/audio/android/audio_record_input.h"
 #include "media/audio/android/opensles_input.h"
 #include "media/audio/android/opensles_output.h"
 #include "media/audio/audio_manager.h"
@@ -111,10 +112,13 @@ AudioParameters AudioManagerAndroid::GetInputStreamParameters(
       base::android::AttachCurrentThread(), GetNativeOutputSampleRate(),
       ChannelLayoutToChannelCount(channel_layout));
 
-  return AudioParameters(
+  AudioParameters params(
       AudioParameters::AUDIO_PCM_LOW_LATENCY, channel_layout,
       GetNativeOutputSampleRate(), 16,
       buffer_size <= 0 ? kDefaultInputBufferSize : buffer_size);
+  params.set_use_platform_aec(Java_AudioManagerAndroid_isPlatformAECSupported(
+      base::android::AttachCurrentThread()));

[henrika (OOO until Aug 14), 2013/12/06 22:51:57]

Any chance you would consider following the example of an old programmer and use
caching here: JNIEnv* env = AttachCurrentThread();

[ajm, 2013/12/10 06:37:16]

Absolutely :)

+  return params;
 }
 
 AudioOutputStream* AudioManagerAndroid::MakeAudioOutputStream(
@@ -189,7 +193,14 @@ AudioInputStream* AudioManagerAndroid::MakeLowLatencyInputStream(
   // device, i.e., this selection does also switch the output device.
   // All input and output streams will be affected by the device selection.
   SetAudioDevice(device_id);
-  return new OpenSLESInputStream(this, params);
+  if (params.use_platform_aec()) {
+    // The platform AEC can only be enabled through the AudioRecord path.
+    DVLOG(1) << "Creating AudioRecordInputStream";
+    return new AudioRecordInputStream(this, params);
+  } else {
+    DVLOG(1) << "Creating OpenSLESInputStream";
+    return new OpenSLESInputStream(this, params);
+  }
 }
 
 int AudioManagerAndroid::GetOptimalOutputFrameSize(int sample_rate,