am f98197a7: Make sure the message dispatcher stays around until after OMX_FreeHandle is finished in case it posts some more messages during shutdown. Clear the source as soon as possible in OMXCodec\'s destructor.

Merge commit 'f98197a7274c2d7da647f52b3d8b0c74492139af' into gingerbread-plus-aosp

* commit 'f98197a7274c2d7da647f52b3d8b0c74492139af':
  Make sure the message dispatcher stays around until after OMX_FreeHandle is finished in case it posts some more messages during shutdown. Clear the source as soon as possible in OMXCodec's destructor.