Support multiple tracks in TV Input framework.

Added API: getTracks/selectTrack/unselectTrack/onTrackInfoChanged
(onVideo/Audio/ClosedCaptionStreamChanged callbacks are removed in favor of onTrackInfoChanged)
Use cases: audio and closed caption track selection
Background: go/tif-multi-track

Bug:14073704, Bug:14121898, Bug: 16049453
Change-Id: I199ed16f690d4e757da0bb30c8bc8222a6fa1d7a