MediaRouter: Use AppCompat's windowNoTitle attribute instead of framework's one

Make chooser dialog inherit AppCompatDialog and use AppCompat's
windowNoTitle attribute instead of framework's one. Because
MediaRouter's theme affects both chooser (Framework dialog) and
controller dialog (AppCompat's AlertDialog), setting
android:windowNoTitle as false may cause the misplaced title bar problem
in the controller dialog.

Bug: 30789373
Test: Applied this fix to CastVideo-android app and observed it's
working well. Tested on K, M, and N devices.
Change-Id: Ied26a6865dd399eadf0938c534eace41f2d96e90
3 files changed