Settings: disable not supported features on third party IME keyboards (2/2)

due that keyboards need to add the WRITE_SETTINGS permission to have
2 of our features working on 4.3 third party apps can break if they
do not set it.

Check the current active input method for the permission and disable
it if the permission is not present

Change-Id: Id1707089114f0b43e0cb01ca072e6e588b3b02c8

Conflicts:
	res/values/strings.xml
	src/com/android/settings/slim/KeyboardInputSettings.java
	src/com/android/settings/slim/PieTriggerSettings.java