RemoteControlClient defines two listener interfaces for playback
position, one to let the framework query the current playback
position, the other to request playback to seek to a given
position.
Updated IRemoteControlDisplay interface to support passing info
about whether the user of RemoteControlClient can provide a
playback position, and receive a new one.
Updated implementations of IRemoteControlDisplay to new
interface.
Bug 8120740
Change-Id: I1a5a969da4d0f8c9ad27f691919dd08f8653982b
3261b537c5