Fix frontOfTask assignment.

If all activities of a given stack were finishing, no activity was
marked as front-of-task. This confused ActivityManager, so make sure
there's always exactly one activity marked as front-of-task.

https://android-review.googlesource.com/#/c/98918

Change-Id: I087cbe10280d4a60aa5ccfaefe24a223523fb3f2
Base: QuickSettings: fix text size on landscape

Change-Id: I043ee71aa8b4e74fd8038fca7613e22b73c81ff5
Base: Allow unregister Callback and Controller

Battery, Bluetooth, Network, Location controller
always set callback without release them if callback owner is missing

add this method to unregister the callback to prevent memory leak

fix whitespace

Change-Id: I0d6451ddfb681bd5301e7958e20d2462d4a82039
Merge "Fix frontOfTask assignment." into android-4.4
Merge remote-tracking branch 'omnirom/android-4.4' into Kitkat