Distinguish discontinuities w/ a format change from those without.

Shutdown decoders as needed in anticipation of a format change, otherwise just flush.

Change-Id: Ieb04f8aa8658569b091409c4903075fd496e5abb
diff --git a/media/libmediaplayerservice/nuplayer/NuPlayer.h b/media/libmediaplayerservice/nuplayer/NuPlayer.h
index fad1ce1..d4e7428 100644
--- a/media/libmediaplayerservice/nuplayer/NuPlayer.h
+++ b/media/libmediaplayerservice/nuplayer/NuPlayer.h
@@ -79,6 +79,7 @@
         NONE,
         AWAITING_DISCONTINUITY,
         FLUSHING_DECODER,
+        FLUSHING_DECODER_FORMATCHANGE,
         SHUTTING_DOWN_DECODER,
         FLUSHED,
         SHUT_DOWN,
@@ -104,6 +105,8 @@
 
     void finishFlushIfPossible();
 
+    static bool IsFlushingState(FlushStatus state, bool *formatChange = NULL);
+
     DISALLOW_EVIL_CONSTRUCTORS(NuPlayer);
 };