am d476e942: am f18cce44: (-s ours) am ef4cd0a4: am d3831760: DO NOT MERGE: Lock drm plugin API calls globally, not per MediaDrm instance

* commit 'd476e942d2e7fb50c086b26b3e50636e55eb0e33':
  DO NOT MERGE: Lock drm plugin API calls globally, not per MediaDrm instance