Better handling of codec initialization failure in the player and thumbnail extractor. Return a runtime error instead of asserting if the software MPEG4/H.263 decoder fails to initialize.

Change-Id: I5cba02ee85a41e43c2623053de40f26e2cf2efe4
related-to-bug: 2699505
diff --git a/media/libstagefright/AwesomePlayer.cpp b/media/libstagefright/AwesomePlayer.cpp
index f668caa..274dad9 100644
--- a/media/libstagefright/AwesomePlayer.cpp
+++ b/media/libstagefright/AwesomePlayer.cpp
@@ -822,7 +822,12 @@
         CHECK(mVideoTrack->getFormat()->findInt32(kKeyWidth, &mVideoWidth));
         CHECK(mVideoTrack->getFormat()->findInt32(kKeyHeight, &mVideoHeight));
 
-        mVideoSource->start();
+        status_t err = mVideoSource->start();
+
+        if (err != OK) {
+            mVideoSource.clear();
+            return err;
+        }
     }
 
     return mVideoSource != NULL ? OK : UNKNOWN_ERROR;