hwc: Set full screen aspect ratio deviation within tolerance level

1. Set tagged video layer to be full screen on external, if the
   deviation between aspect ratio of external and aspect ratio of
   video layer is within the tolerance level.
2. Set sys.hwc.windowbox_aspect_ratio_tolerance property to change the
   tolerance level.

Example:
   Set sys.hwc.windowbox_aspect_ratio_tolerance to 5 for +/- 5%
   tolerance level

Change-Id: I5b3e962dfa1c9fc19036e42cb4599d0490b04da9
2 files changed