Fix FloatingActionButton.setBackgroundTint* not working

Caused by the move to AppCompatImageButton. Happens due
to AppCompat's own background tinting overriding things.
Fixed by moving back to our own tinting. Had to add
support to use AppCompat's ImageHelper to enable vector
icon support.

BUG: 27372244
Change-Id: Ia06bea72796e7154bae50c65ef6dfe91158e3bf6
7 files changed