Add SET_WALLPAPER permission to SystemUI

If an exception is thrown in updateWallpaperLocked, a call to
WallpaperManager.clear() is made.  This requires the SET_WALLPAPER
permission and will throw a SecurityException if that permission
is not granted to SystemUI.

Change-Id: I61811b65dcfe8b15f0e9030f7aa6d1dc09cea351
SystemUI: Restore bounds when loading new gradient

This fixes an issue introduced with the reloading of the nav bar
transitions after a theme change in Change-Id: I256afc30fc018ea752769029c5246bc7310c23a6

Change-Id: I648039506b826583d554b2a0cf4f6ab9a9bb1de8
Merge "Add SET_WALLPAPER permission to SystemUI" into kitkat
Merge "SystemUI: Restore bounds when loading new gradient" into kitkat