Fix registering global priority sessions

We were never setting a global priority session due to a change in
the way sessions were registered. This makes sure a global session
gets set correctly.

bug:16930866
Change-Id: I859846c9265e98bb1a37ff9d22808137e787ce18

Author: RoboErikG

services/core/java/com/android/server/media/MediaSessionService.java

@@ -87,7 +87,6 @@ public class MediaSessionService extends SystemService implements Monitor {
     private IAudioService mAudioService;
     private ContentResolver mContentResolver;
 
-    private MediaSessionRecord mPrioritySession;
     private int mCurrentUserId = -1;
 
     // Used to notify system UI when remote volume was changed. TODO find a
@@ -125,18 +124,6 @@ public void updateSession(MediaSessionRecord record) {
                 return;
             }
             mPriorityStack.onSessionStateChange(record);
-            if (record.isSystemPriority()) {
-                if (record.isActive()) {
-                    if (mPrioritySession != null) {
-                        Log.w(TAG, "Replacing existing priority session with a new session");
-                    }
-                    mPrioritySession = record;
-                } else {
-                    if (mPrioritySession == record) {
-                        mPrioritySession = null;
-                    }
-                }
-            }
         }
         mHandler.post(MessageHandler.MSG_SESSIONS_CHANGED, record.getUserId(), 0);
     }
@@ -258,9 +245,6 @@ private void destroySessionLocked(MediaSessionRecord session) {
 
         mPriorityStack.removeSession(session);
         mAllSessions.remove(session);
-        if (session == mPrioritySession) {
-            mPrioritySession = null;
-        }
 
         try {
             session.getCallback().asBinder().unlinkToDeath(session, 0);
@@ -716,10 +700,6 @@ public void dump(FileDescriptor fd, final PrintWriter pw, String[] args) {
             pw.println();
 
             synchronized (mLock) {
-                pw.println("Session for calls:" + mPrioritySession);
-                if (mPrioritySession != null) {
-                    mPrioritySession.dump(pw, "");
-                }
                 int count = mAllSessions.size();
                 pw.println(count + " Sessions:");
                 for (int i = 0; i < count; i++) {

services/core/java/com/android/server/media/MediaSessionStack.java

@@ -63,9 +63,6 @@ public class MediaSessionStack {
      */
     public void addSession(MediaSessionRecord record) {
         mSessions.add(record);
-        if ((record.getFlags() & MediaSession.FLAG_EXCLUSIVE_GLOBAL_PRIORITY) != 0) {
-            mGlobalPrioritySession = record;
-        }
         clearCache();
     }
 
@@ -110,6 +107,9 @@ public boolean onPlaystateChange(MediaSessionRecord record, int oldState, int ne
      * @param record The record that changed.
      */
     public void onSessionStateChange(MediaSessionRecord record) {
+        if ((record.getFlags() & MediaSession.FLAG_EXCLUSIVE_GLOBAL_PRIORITY) != 0) {
+            mGlobalPrioritySession = record;
+        }
         // For now just clear the cache. Eventually we'll selectively clear
         // depending on what changed.
         clearCache();
@@ -220,6 +220,7 @@ public void dump(PrintWriter pw, String prefix) {
         ArrayList<MediaSessionRecord> sortedSessions = getPriorityListLocked(false, 0,
                 UserHandle.USER_ALL);
         int count = sortedSessions.size();
+        pw.println(prefix + "Global priority session is " + mGlobalPrioritySession);
         pw.println(prefix + "Sessions Stack - have " + count + " sessions:");
         String indent = prefix + "  ";
         for (int i = 0; i < count; i++) {