DO NOT MERGE: drm_hwcomposer: Move SeparateLayers into a member function am: 3498225e33  -s ours
am: f625e80960

* commit 'f625e80960917ddfdec7292d0cb25bef86460d49':

Change-Id: Ie72266caeb72aac65b8bf2019b624ee5b9ea2dcd