Add MODIFY_AUDIO_SETTINGS permission in Android manifest and implementation in audio manager.

media/audio/android/audio_manager_android.cc

Index: media/audio/android/audio_manager_android.cc
===================================================================
--- media/audio/android/audio_manager_android.cc	(revision 187192)
+++ media/audio/android/audio_manager_android.cc	(working copy)
@@ -5,6 +5,7 @@
 #include "media/audio/android/audio_manager_android.h"
 
 #include "base/logging.h"
+#include "jni/AudioManagerAndroid_jni.h"
 #include "media/audio/android/opensles_input.h"
 #include "media/audio/android/opensles_output.h"
 #include "media/audio/audio_manager.h"
@@ -60,12 +61,14 @@
 AudioOutputStream* AudioManagerAndroid::MakeLinearOutputStream(
       const AudioParameters& params) {
   DCHECK_EQ(AudioParameters::AUDIO_PCM_LINEAR, params.format());
+  SetAudioMode(kAudioModeNormal);

[no longer working on chromium, 2013/03/11 16:07:54]

could you please explain why MakeLinearOutputStream and
MakeLowLatencyOutputStream are using different modes?

   return new OpenSLESOutputStream(this, params);
 }
 
 AudioOutputStream* AudioManagerAndroid::MakeLowLatencyOutputStream(
       const AudioParameters& params) {
   DCHECK_EQ(AudioParameters::AUDIO_PCM_LOW_LATENCY, params.format());
+  SetAudioMode(kAudioModeInCommunication);
   return new OpenSLESOutputStream(this, params);
 }
 
@@ -81,6 +84,11 @@
   return new OpenSLESInputStream(this, params);
 }
 
+// static
+bool AudioManagerAndroid::RegisterAudioManager(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
 AudioParameters AudioManagerAndroid::GetPreferredOutputStreamParameters(
     const AudioParameters& input_params) {
   // TODO(xians): figure out the right output sample rate and sample rate to
@@ -116,4 +124,13 @@
       sample_rate, bits_per_sample, buffer_size);
 }
 
+void AudioManagerAndroid::SetAudioMode(int mode) {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  DCHECK(env);
+  jobject context = base::android::GetApplicationContext();
+  DCHECK(context);
+
+  Java_AudioManagerAndroid_setMode(env, context, mode);
+}
+
 }  // namespace media