Launch theme chooser that supports cyngn.intent.category.APP_THEMES

If we receive an ActivityNotFound exception we will simply show
the theme settings fragment.

Change-Id: I38bf6857125cdeda310e3bb5614fd6adaba8265f
Signed-off-by: anerikg <anerikgames@gmail.com>

Conflicts:
	src/com/android/settings/Settings.java