automerge: 2b36779 * commit '2b36779f30a511cc4439a519c95963280a779fdc': Doc change: refactor GCM docs to be platform-agnostic.
automerge: 2b36779 * commit '2b36779f30a511cc4439a519c95963280a779fdc': Doc change: refactor GCM docs to be platform-agnostic.