am fcfe6f5c: am bd94aff2: Merge changes If4c38bfe,Id9878186 into lmp-mr1-dev automerge: b1d52e1

* commit 'fcfe6f5c7e12548d20c31bcad4db5089d23b78d8':
  Update metadata artwork and uri docs
  skip MediaController callbacks if it's been unregistered