[Media TTT] Add the #closeToReceiverToEndCast callback.

Bug: 203800643
Bug: 203800347
Test: verify `adb shell cmd statusbar media-ttt-chip-add-sender
Tablet MoveCloserToStartCast` triggers start cast chip
Test: verify `adb shell cmd statusbar media-ttt-chip-add-sender
Tablet MoveCloserToEndCast` triggers end cast chip
Test: media.taptotransfer tests

Change-Id: I1be9f1ab9785b47c4b2321e48a61e0985613e112
8 files changed