NuPlayerRenderer: discard delayed audio EOS notification when renderer being flushed.

Bug: 23226641
Change-Id: I21fc7b8fd66ceefe70b110987e472f035198d1ae
diff --git a/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.h b/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.h
index 58bf121..955f58a 100644
--- a/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.h
+++ b/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.h
@@ -148,6 +148,7 @@
     int32_t mVideoQueueGeneration;
     int32_t mAudioDrainGeneration;
     int32_t mVideoDrainGeneration;
+    int32_t mAudioEOSGeneration;
 
     sp<MediaClock> mMediaClock;
     float mPlaybackRate; // audio track rate