Api updates to MediaSession components

-renames get/setBufferPosition to get/setBufferedPosition
-renames getLaunchActivity to getSessionActivity
-adds doc link to setVolumeTo flags param
-renames setLaunchActivity to setSessionActivity
-hides setMediaRouter
-moves PLAYBACK_TYPE_ constants to MediaController.AudioInfo
-adds addOnActiveSessionsChangedListener version with a handler parameter
-renames AudioInfo to PlaybackInfo

bug:17114404
Change-Id: I0fbfe4eb979cb2af98e3f13095c654bb131f7ae5
diff --git a/services/core/java/com/android/server/media/MediaSessionStack.java b/services/core/java/com/android/server/media/MediaSessionStack.java
index fec11fba..a9bc818 100644
--- a/services/core/java/com/android/server/media/MediaSessionStack.java
+++ b/services/core/java/com/android/server/media/MediaSessionStack.java
@@ -16,6 +16,7 @@
 
 package com.android.server.media;
 
+import android.media.session.MediaController.PlaybackInfo;
 import android.media.session.PlaybackState;
 import android.media.session.MediaSession;
 import android.os.UserHandle;
@@ -209,7 +210,7 @@
         int size = records.size();
         for (int i = 0; i < size; i++) {
             MediaSessionRecord record = records.get(i);
-            if (record.getPlaybackType() == MediaSession.PLAYBACK_TYPE_REMOTE) {
+            if (record.getPlaybackType() == PlaybackInfo.PLAYBACK_TYPE_REMOTE) {
                 return record;
             }
         }