drm_hwcomposer: Use hw planes + drm atomic interface

Replace the basic, single overlay, modeset/flip implementation with
a new Compositor instantiation for drm. The new compositor uses the
drm atomic interface to composite layers to multiple hardware planes.

This change also introduces an importer argument in
Compositor::CreateComposition. By specifying the importer, Compositor
instances are responsible for cleaning up buffer objects submitted
via Composition::AddLayer.

Change-Id: Ic292829cd93475d754294b00428de132301092b2
Signed-off-by: Sean Paul <seanpaul@chromium.org>
10 files changed