[21/n] Reduce dependencies from LetterboxUiController

Reduces dependencies from LetterboxUiController.

Introduce isChangeEnabled() to AppCOmpatUtils.

Flag: EXEMPT refactor
Bug: 346264992
Test: atest WmTests:LetterboxUControllerTest
Test: atest WmTests:AppCompatOrientationOverridesTest

Change-Id: Iddc996a96a5dfe43306553b3c71dc2cb5fc012a3
14 files changed