Add dialog and controller for TileServiceRequest

This adds the SystemUI side. As there's no API, it's triggered using
CommandRegistry and outputs response to logcat.

The design of the dialog is not final, so measures and styles will be
changed in a future CL.

Test: atest TileRequestDialogTest TileServiceRequestControllerTest
Test: manual
Fixes: 196056024

Change-Id: I5a52b7cd9db6a7fc79a8751e7702be8c005b8def