Policy Hal:  Fix video stutters.

  NULL cannot be used as a third arg for property_get.
  This was causing the offload properties to be ignored
  forcing offload during streaming video.
   Thank you Arcee

Change-Id: I34cb6ffb60a11ad0eb346c99ce7ec96f323c54ae

Patchset: 1
http://review.cyanogenmod.org/#/c/59300/