Fix for "Android audio playout doesn't support non-call media stream"

webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioUtils.java

Index: webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioUtils.java
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 9d7a600190c5151e689a75c8f4d156f2249ef2bd..f08e11dad88833cce0efe144176025214ac8920e 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
@@ -193,5 +193,37 @@ public final class WebRtcAudioUtils {
         permission,
         Process.myPid(),
         Process.myUid()) == PackageManager.PERMISSION_GRANTED;
+  }
+
+  // Convert the provided audio |mode| into most suitable audio output stream
+  // type. The stream type is used for creating audio streams and for volume
+  // changes. It is essential that the mode and type are in-line to ensure
+  // correct behavior. If for example a STREAM_MUSIC type of stream is created
+  // in a MODE_IN_COMMUNICATION mode, audio will be played out and the volume
+  // icon will look OK but the actual volume will not be changed when the user
+  // changes the volume slider.
+  // TODO(henrika): there is currently no mapping to STREAM_ALARM, STREAM_DTMF,
+  // or STREAM_NOTIFICATION types since I am unable to see a reason for using
+  // them. There are only four different modes.
+  public static int getOutputStreamTypeFromAudioMode(int mode) {
+    Logging.d(TAG, "getOutputStreamTypeFromAudioMode(mode=" + mode + ")");
+    switch (mode) {
+      case AudioManager.MODE_NORMAL:
+        // The audio stream for music playback.
+        Logging.d(TAG, "AudioManager.STREAM_MUSIC");
+        return AudioManager.STREAM_MUSIC;
+      case AudioManager.MODE_RINGTONE:
+        // Audio stream for the phone ring.
+        Logging.d(TAG, "AudioManager.STREAM_RING");
+        return AudioManager.STREAM_RING;
+      case AudioManager.MODE_IN_CALL:
+      case AudioManager.MODE_IN_COMMUNICATION:
+        // Audio stream for phone calls.
+        Logging.d(TAG, "AudioManager.STREAM_VOICE_CALL");
+        return AudioManager.STREAM_VOICE_CALL;
+      default:
+        Logging.d(TAG, "AudioManager.USE_DEFAULT_STREAM_TYPE");
+        return AudioManager.USE_DEFAULT_STREAM_TYPE;
     }
+  }
 }