AppRTCDemo (Android): built-in AEC should be enabled if device supports it and in combination with Java-based audio layer

BUG=4034
R=andrew@webrtc.org, perkj@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/32179004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@7849 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/modules/audio_device/android/opensles_input.h

@@ -118,6 +118,10 @@ class OpenSlesInput {
   // Attach audio buffer
   void AttachAudioBuffer(AudioDeviceBuffer* audioBuffer);
 
+  // Built-in AEC is only supported in combination with Java/AudioRecord.
+  bool BuiltInAECIsAvailable() const { return false; }
+  int32_t EnableBuiltInAEC(bool enable) { return -1; }
+
  private:
   enum {
     kNumInterfaces = 2,