SnapdragonCamera: Keep screen on when recording the video

Add the actions to keep the screen on or off.
(1) We always keep the screen on when click video button for recording
    video.
(2) We keep the screen on for 2 mins when click video button for stop
    recording video.
(3) We clear the flag(FLAG_KEEP_SCREEN_ON) when exit
    the camera.

CRs-Fixed: 1095512
change-Id: I283c29882f0654315536afbafc5072491343a38f
1 file changed