Use the main thread to update alignment indication

The alignment status is reported from WLC-HAL level and runs
on another thread. It may cause CalledFromWrongThreadException,
if use that thread to update UI directly.

Bug: 146770234
Test: atest SystemUITests:KeyguardIndicationControllerTest
Change-Id: I89bf1c188d6ba094106e059f1590c9eaf3703bb8