Instead of not feeding the AudioTrack any data after EOS, play silence instead.

Change-Id: I9aa797cf5bb58eefed51d732f4e5d09450551158
related-to-bug: 3347428

media/libstagefright/AudioPlayer.cpp

@@ -286,7 +286,9 @@ size_t AudioPlayer::fillBuffer(void *data, size_t size) {
     }
 
     if (mReachedEOS) {
-        return 0;
+        memset(data, 0, size);
+
+        return size;
     }
 
     size_t size_done = 0;