Don't send OnCompletion events when looping

AwesomePlayer never did, and neither should NuPlayer.

Bug: 18656047
Change-Id: Ia9abe42cfe6ea643633cec859e9da770092569bb
diff --git a/media/libmediaplayerservice/nuplayer/NuPlayerDriver.cpp b/media/libmediaplayerservice/nuplayer/NuPlayerDriver.cpp
index 7370224..6419be0 100644
--- a/media/libmediaplayerservice/nuplayer/NuPlayerDriver.cpp
+++ b/media/libmediaplayerservice/nuplayer/NuPlayerDriver.cpp
@@ -747,7 +747,8 @@
                         // the last little bit of audio. If we're looping, we need to restart it.
                         mAudioSink->start();
                     }
-                    break;
+                    // don't send completion event when looping
+                    return;
                 }
 
                 mPlayer->pause();