Avoid automatically mirroring Drawable of CustomTile

Developers of custom tiles should decide whether
the Drawable of their own tiles should be automatically mirrored.
So State#autoMirrorDrawable should be false by default.

Bug: 30930145
Test: manual - change to RTL language and open Quick Settings

Change-Id: Ia3fd8c2aeddb4a27b9ecfaaf52edbcce01fd7f48