android/surface_control: Add usage flag required for use with HwC.

Hardware composer requires buffers to have a flag set if they are going
to be used as overlays. The framework currently sets it for buffers it
creates internally. Make sure to also set it for buffers allocated by
Chrome used with the SurfaceControl API.

R=liberato@chromium.org, piman@chromium.org

Bug: 943706
Change-Id: I9677c4833cf711ead8e5467e64a395d3c2ae56e4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1529408
Reviewed-by: Antoine Labour <piman@chromium.org>
Reviewed-by: Frank Liberato <liberato@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Khushal <khushalsagar@chromium.org>
Auto-Submit: Khushal <khushalsagar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#642839}
4 files changed