Revert "Revert "Fix overactive media routing""

This reverts commit 0aec178b7e66a29a22e90415faa15fb5f01aaef2.

Bug: 65376604
Test: manual and media cts
Change-Id: Ifd20848b406a1c51356c0b852274ba85b7062fdc
diff --git a/services/core/java/com/android/server/media/MediaSessionStack.java b/services/core/java/com/android/server/media/MediaSessionStack.java
index d9fe72e..719ec36 100644
--- a/services/core/java/com/android/server/media/MediaSessionStack.java
+++ b/services/core/java/com/android/server/media/MediaSessionStack.java
@@ -75,7 +75,7 @@
      */
     private final List<MediaSessionRecord> mSessions = new ArrayList<MediaSessionRecord>();
 
-    private final AudioPlaybackMonitor mAudioPlaybackMonitor;
+    private final AudioPlayerStateMonitor mAudioPlayerStateMonitor;
     private final OnMediaButtonSessionChangedListener mOnMediaButtonSessionChangedListener;
 
     /**
@@ -84,7 +84,6 @@
      */
     private MediaSessionRecord mMediaButtonSession;
 
-    private MediaSessionRecord mCachedDefault;
     private MediaSessionRecord mCachedVolumeDefault;
 
     /**
@@ -93,8 +92,8 @@
     private final SparseArray<ArrayList<MediaSessionRecord>> mCachedActiveLists =
             new SparseArray<>();
 
-    MediaSessionStack(AudioPlaybackMonitor monitor, OnMediaButtonSessionChangedListener listener) {
-        mAudioPlaybackMonitor = monitor;
+    MediaSessionStack(AudioPlayerStateMonitor monitor, OnMediaButtonSessionChangedListener listener) {
+        mAudioPlayerStateMonitor = monitor;
         mOnMediaButtonSessionChangedListener = listener;
     }
 
@@ -187,13 +186,13 @@
         if (DEBUG) {
             Log.d(TAG, "updateMediaButtonSessionIfNeeded, callers=" + Debug.getCallers(2));
         }
-        IntArray audioPlaybackUids = mAudioPlaybackMonitor.getSortedAudioPlaybackClientUids();
+        IntArray audioPlaybackUids = mAudioPlayerStateMonitor.getSortedAudioPlaybackClientUids();
         for (int i = 0; i < audioPlaybackUids.size(); i++) {
             MediaSessionRecord mediaButtonSession =
                     findMediaButtonSession(audioPlaybackUids.get(i));
             if (mediaButtonSession != null) {
                 // Found the media button session.
-                mAudioPlaybackMonitor.cleanUpAudioPlaybackUids(mediaButtonSession.getUid());
+                mAudioPlayerStateMonitor.cleanUpAudioPlaybackUids(mediaButtonSession.getUid());
                 if (mMediaButtonSession != mediaButtonSession) {
                     updateMediaButtonSession(mediaButtonSession);
                 }
@@ -216,7 +215,7 @@
         for (MediaSessionRecord session : mSessions) {
             if (uid == session.getUid()) {
                 if (session.getPlaybackState() != null && session.isPlaybackActive() ==
-                        mAudioPlaybackMonitor.isPlaybackActive(session.getUid())) {
+                        mAudioPlayerStateMonitor.isPlaybackActive(session.getUid())) {
                     // If there's a media session whose PlaybackState matches
                     // the audio playback state, return it immediately.
                     return session;
@@ -376,7 +375,6 @@
     }
 
     private void clearCache(int userId) {
-        mCachedDefault = null;
         mCachedVolumeDefault = null;
         mCachedActiveLists.remove(userId);
         // mCachedActiveLists may also include the list of sessions for UserHandle.USER_ALL,