camera: add power mode support

Based on commit 7036d66bec7697160ba1b2e255f1e7fae0c8c435 from CAF,
branch ics_chocolate.

Change-Id: I8a60668b18980fd5e6f9dd341db5a8a63deb99d0
Port "Option to control cursor in text fields using volume keys (1/2)"

This feature is moved to framework so it also works with third party keyboards.
Patch Set 3: Added missin @hide statements

Change-Id: I8e20240e7bee5351ab20bb3d701eb95a5fd3e112
Fix derp in WindowManager

Signed-off-by: travp624 <travp624@gmail.com>