bluetooth: Don't crash when the local adapter is not set

In devices where bluetooth is not working (like the emulator or devices
in development), the bluetooth Settings crashes when closing the activity.

Most of the code checks for the nullability of the local adapter except
for this particular piece. This is usually not a worry for production
devices and I wouldn't usually worry about this but since the rest of the
code performs the nullability check it seems silly to crash onPause.

Change-Id: I7c1d3b43969b516336be770957008ef2054d312f
TrustedCredentials: Don't crash when the activity is paused

If you press Settings -> Security -> Trusted Credentials, then press
 back before the loading finishes, the loader async task will still
try to dereference the activity which will cause an NPE.

This patch fixes that by getting and holding a reference to the
context in the beggining and bailing early if it is null.

Change-Id: Ie03734d5f184821df5d8729fc4a16eb51cdeebf5
bluetooth: Show a refresh icon on the select devices screen

The refresh menu is hidden behind an overflow which is
pointless. This patch shows the refresh icon if there is
enough room.

Change-Id: I35f19c42054b05388f7b8fcb82e0f3bd60e2d618
Setting: add app move to external storage

Add support tp move APP to external storage.

Change-Id: I9d8fef2df2f36b4d8b611d8ffe87990407b44742
Settings: Add per app controls for LP keyguard notifications (2/2)

Nice done by google but the UX is a problem especially for ppl who are using a lot apps and just want
to see from important apps the notifications on the lockscreen.

This commit adds the ability to

- enable/disable per app the keyguard notification at all
- enable/disable per app ongoing notifications on the keyguard

We handle this over the app policy conf file like the other per app notification options

Change-Id: Ie4966f9048718c080571935796258625413f7344

(cherry picked from commit 4c77d39a4cd5ea6c27dab7c5a44ca7eae30aa435)
Add consistency: SwitchPerferences over CheckboxPreferences

- Developer Settings
- Accessibility
- Date and Time
- Button Settings

Credit: @kufikugel

Change-Id: I830adeb7dfd94726594b9d7879776c6717bed3b9
Settings: add toggle for QS quick pulldown (2/2)

Change-Id: Id7a422d5780c14e569cd35759851980baa154b46