hwc: In PTOR, offset depends on stride calculated by gralloc

1. In PTOR feature, offset for the second overlap layer on render
buffer, depends on stride calculated by gralloc for RGBA (4 bpp).

2. If mCopyBit object exists for external, we need setReleaseFd()

Change-Id: I74e365def2a6e540b2f2ba2b294b6b1e00e0ea96
hwc: 8084: Split videos with width > 2048 if source split absent

Split video with width > 2048 only if source split is absent, and
the relevant system property is set.
In source split the video is split evenly anyway.

Change-Id: Iab0af427756d32120a160787ecfb7c974dbbeea1
(cherry picked from commit c6f6ce9981e095965c7aec262954f5afbd24043a)