Update the supported type in ACCESSIBILITY_BUTTON_MODE according to navigation...

Update the supported type in ACCESSIBILITY_BUTTON_MODE according to navigation gestural mode or button mode

Root cause: From the user feedback, accessibiltiy gesture has more
benifits than floating accessibility button especially to low vision users.

Solution: Bring back accessibility gesture to be one of the options of
the accessibility button, then update to supported type according to navigation gestural mode or button mode. ACCESSIBILITY_BUTTON_MODE_NAVIGATION_BAR is incompatible under gestural mode; ACCESSIBILITY_BUTTON_MODE_GESTURE is incompatible under non gestural mode; ACCESSIBILITY_BUTTON_MODE_FLOATING_MENU is compatible under both mode.

Bug: 190563948
Test: install new SettingsProvider.apk & adb reboot & manual test
Change-Id: I9ac163603112bc899f64164bee5752a5249ed0dc