In order to recover from video lagging behind audio, drop avc frames

that are not referenced by other frames before feeding them into the decoder.

Change-Id: I822190af8f8329567bff8da1ea23136d0a765481
diff --git a/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.h b/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.h
index 44c5d44..268628b 100644
--- a/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.h
+++ b/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.h
@@ -101,6 +101,7 @@
     bool mPaused;
 
     int64_t mLastPositionUpdateUs;
+    int64_t mVideoLateByUs;
 
     bool onDrainAudioQueue();
     void postDrainAudioQueue(int64_t delayUs = 0);
@@ -118,6 +119,7 @@
     void notifyEOS(bool audio, status_t finalResult);
     void notifyFlushComplete(bool audio);
     void notifyPosition();
+    void notifyVideoLateBy(int64_t lateByUs);
 
     void flushQueue(List<QueueEntry> *queue);
     bool dropBufferWhileFlushing(bool audio, const sp<AMessage> &msg);