Do not set user rotation from rotation callback when docked.

This changelist prevents RotationButtonController from changing the
user chosen rotation from an external rotation change. This suppression
only is in effect when docked.

Test: manual based on the repro steps in bug.
Fixes: 231598013
Change-Id: Ia191c024a68ffc9bc9e8bbff2c11c29fc35cc49d