NuPlayer: Discard seeks when source and decoders are NULL

Problem occurs when loop mode asynchronously seeks to the
start of the source after a MediaPlayer::reset().

Bug: 17379148
Change-Id: I50bfe65a753afffb1d478db54c76067a9c61a0ae
diff --git a/media/libmediaplayerservice/nuplayer/NuPlayerDriver.cpp b/media/libmediaplayerservice/nuplayer/NuPlayerDriver.cpp
index 2423f5f..09324ae 100644
--- a/media/libmediaplayerservice/nuplayer/NuPlayerDriver.cpp
+++ b/media/libmediaplayerservice/nuplayer/NuPlayerDriver.cpp
@@ -626,7 +626,7 @@
     switch (msg) {
         case MEDIA_PLAYBACK_COMPLETE:
         {
-            if (mLooping) {
+            if (mLooping && mState != STATE_RESET_IN_PROGRESS) {
                 mLock.unlock();
                 mPlayer->seekToAsync(0);
                 mLock.lock();