settings: port ime selector notification toggle

framework changes already present

Change-Id: Iffd7cf5c3eb7368974e792194e9ebe8a75ca35b7

Settings: Fix NPE when CM IME switcher is disabled

Change-Id: I8c1dc5874accc6d1340dc46a58867d97f708aeb7

Conflicts:

	res/xml/language_settings.xml
Improve app op details layout.

Change-Id: I38a2c3679633ae85aec61703ab933410775bb336