GitLab

This CL converts MediaCapsObserverPtr to new Mojo types. It
uses Receiver, ReceiverSet, RemoteSet, and PendingRemote or Remote
instead of Binding, BindingSet, InterfacePtrSet and
MediaCapsObserverPtr.

Bug: 955171
Change-Id: I26460b5c0a13f858997c6141d6ca437cb84a674d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1786704
Commit-Queue: Julie Kim <jkim@igalia.com>
Reviewed-by: Sam McNally <sammc@chromium.org>
Reviewed-by: Oksana Zhuravlova <oksamyt@chromium.org>
Reviewed-by: Luke Halliwell <halliwell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#695540}