Add PowerManager integration for button and keyboard backlight.

Allows setting button and keyboard backlight brightness as well as
button timeout.

Change-Id: I550cccafc0a8f90d6347de9261adb26b75955cc4
QuickSettings : Fix update issue if linked

Currently ribbon does not reflect updates to QS if they're linked.
This patchset addresses that.

Change-Id: I3787c30892c13dbcb7e5c48ff99cd2220b638302
Hide new non-standard APIs and permission

These were breaking builds due to the public API modification

Change-Id: I603fcf0601f40fb315086859aa03ef5b7ec39248
Merge "Add PowerManager integration for button and keyboard backlight." into cm-10.2
Merge remote-tracking branch 'upstream/cm-10.2' into cm-10.2