gpu/android : Add support for partial swap with surface control.

Add support for PostSubBuffer to GLSurfaceEGLSurfaceControl. This should
allow the display compositor to draw the minimum sub-rect necessary from
the damage tracking in BufferQueue on the client-side, and also to pass
this damage rect to the framework.

R=piman@chromium.org

Bug: 926020
Change-Id: I73d3320cab68250d4c6865bf21c5531682d8bf61
Reviewed-on: https://chromium-review.googlesource.com/c/1457467
Commit-Queue: Khushal <khushalsagar@chromium.org>
Commit-Queue: Antoine Labour <piman@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Auto-Submit: Khushal <khushalsagar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#629852}
void CompositorImpl::DidInitializeLayerTreeFrameSink() {
  layer_tree_frame_sink_request_pending_ = false;
  has_layer_tree_frame_sink_ = true;
  for (auto& frame_sink_id : pending_child_frame_sink_ids_)
    AddChildFrameSink(frame_sink_id);

  pending_child_frame_sink_ids_.clear();
}

void CompositorImpl::DidInitializeLayerTreeFrameSink() {
  layer_tree_frame_sink_request_pending_ = false;
  has_layer_tree_frame_sink_ = true;
  for (auto& frame_sink_id : pending_child_frame_sink_ids_)
    AddChildFrameSink(frame_sink_id);

  pending_child_frame_sink_ids_.clear();
}
