In the RemoteController implementation, the inner class that
implements the IRemoteControlDisplay interface must have a weak
link to the RemoteController instance with which it is associated,
as MediaFocusControl and RemoteControlClient hold a strong
reference to this binder object in a different remote process.
Without a weak reference, any object referencing RemoteController
couldn't be independently garbage collected without a garbage
collection in the remote process.
Bug 8209392
Change-Id: I29e4274c45249b3cb0d3d89417c69e8fe8f62fc4
4348a73bbe