Implement AHardwareBuffer backed sharableImage.

Initial implementation of an AHardwareBuffer backed sharableImage and
corresponding unittests.

Bug: 891060
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
Change-Id: I785a8666c210a21463514b79f8cc253c6b9544d3
Reviewed-on: https://chromium-review.googlesource.com/c/1282442
Commit-Queue: vikas soni <vikassoni@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Reviewed-by: Eric Karl <ericrk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#601016}
7 files changed