Configures page to hide/replace elements that would mention gesture.
Also, provides context when necessary if a setting is disabled by the current button mode.
Demonstration video:
https://x20web.corp.google.com/users/jo/jonesriley/splitShortcut/a11yShortcutSettingsCleanup.mp4
Test: manual, navigate to the Accessibility Button "more options" page in gesture navigation mode. Verify there are no references to gesture.
Bug: 349178639
Flag: android.provider.a11y_standalone_gesture_enabled
Change-Id: I067738d23e74c00bab4010d187820d09013809ad
* No need to call updateState() in onPreferenceChange()
Bug: 274326713
Test: make RunSettingsRoboTests ROBOTEST_FILTER="(AccessibilityButtonGesturePreferenceControllerTest|CaptioningLocalePreferenceControllerTest|CaptioningFontSizeControllerTest|CaptioningTypefaceControllerTest|AccessibilityButtonLocationPreferenceControllerTest|FloatingMenuSizePreferenceControllerTest|SelectLongPressTimeoutPreferenceControllerTest)"
Change-Id: I14a87597a44c5500ff7e676664b67feb9c352494
1. Add gesture preference controller for gesture navigation
2. Auto update the preview illustarion when screen reader is on
3. Auto update accessibility button title for system navigation
Bug: 190563948
Test: make RunSettingsRoboTests ROBOTEST_FILTER=AccessibilityButtonGesturePreferenceControllerTest ROBOTEST_FILTER=AccessibilityButtonPreviewPreferenceControllerTest ROBOTEST_FILTER=AccessibilityLayerDrawableTest ROBOTEST_FILTER=AccessibilityPreferenceControllerTest ROBOTEST_FILTER=AccessibilityButtonFooterPreferenceControllerTest
Change-Id: Ifa98fc029430d86d3143133b3203b239340f2e41
