3/ Listen ONE_HANDED_MODE_ACTIVATED for A11y shortcut action

- Observe ONE_HANDED_MODE_ACTIVATED secure settings key
- Skip action when OneHandedState is in transition
  1. STATE_ENTERING
  2. STATE_EXITING
- Skip action if current OneHandedState = request activate
  1. STATE NONE -> Shortcut request ACTIVATED : StartOneHanded
  2. STATE_ACTIVE -> Shortcut request non ACTIVATED : StopOneHanded
  3. STATE_NONE -> Shortcut request non ACTIVATED : SKip
  4. STATE_ACTIVE -> Shortcut request ACTIVATED : Skip
- Controller will update latest state to secure setting
  ONE_HANDED_MODE_ACTIVATED either trigger by gesture or shortcut

Test: atest WMShellUnitTests
Test: enable shortcut and click
Bug: 182425480
Change-Id: I03bd2679a5a08801efc9868148adfddef87171f4