Aura: Support --enable-partial-swap with --composite-to-mailbox

cc/output/gl_renderer.cc

Index: cc/output/gl_renderer.cc
diff --git a/cc/output/gl_renderer.cc b/cc/output/gl_renderer.cc
index 4519af374cf4d784be4a5c63beaa0f81c8746a6a..558b74d7e608e94a50e3f47fa38f18a8fa5cbe26 100644
--- a/cc/output/gl_renderer.cc
+++ b/cc/output/gl_renderer.cc
@@ -1828,6 +1828,8 @@ void GLRenderer::FinishDrawingFrame(DrawingFrame* frame) {
   if (Settings().compositor_frame_message) {
     CompositorFrame compositor_frame;
     compositor_frame.metadata = client_->MakeCompositorFrameMetadata();
+    compositor_frame.gl_frame_data.reset(new GLFrameData());
+    compositor_frame.gl_frame_data->damage_rect = GetFrameDamage();
     output_surface_->SendFrameToParentCompositor(&compositor_frame);
   }
 }
@@ -1959,15 +1961,7 @@ void GLRenderer::SwapBuffers(const ui::LatencyInfo& latency_info) {
   if (capabilities_.using_partial_swap && client_->AllowPartialSwap()) {
     // If supported, we can save significant bandwidth by only swapping the
     // damaged/scissored region (clamped to the viewport)
-    swap_buffer_rect_.Intersect(client_->DeviceViewport());
-    int flipped_y_pos_of_rect_bottom =
-        client_->DeviceViewport().height() - swap_buffer_rect_.y() -
-        swap_buffer_rect_.height();
-    output_surface_->PostSubBuffer(gfx::Rect(swap_buffer_rect_.x(),
-                                             flipped_y_pos_of_rect_bottom,
-                                             swap_buffer_rect_.width(),
-                                             swap_buffer_rect_.height()),
-                                   latency_info);
+    output_surface_->PostSubBuffer(GetFrameDamage(), latency_info);

[aelias_OOO_until_Jul13, 2013/06/10 22:20:12]

To be clearer about what I was asking for earlier, could you do here:

gfx::Rect frame_damage = GetFrameDamage();
if (frame_damage.size() == SurfaceSize())
  output_surface_->SwapBuffers(latency_info);
else
  output_surface_->PostSubBuffer(GetFrameDamage(), latency_info);

That would match the behavior after my patch.  The reason is that I don't have
access to the "using_partial_swap" setting from the output surface, so I would
just choose based on the rect size.

[aelias_OOO_until_Jul13, 2013/06/10 23:20:20]

On second thought, since this doesn't truly need to be a big blocker, I changed
my other patch to pass another boolean in GLFrameData to preserve the existing
behavior.  We can clean it up later once Mesa is confirmed to work with a
postSubBuffer/prepareTexture mix.

   } else {
     output_surface_->SwapBuffers(latency_info);
   }
@@ -2904,4 +2898,13 @@ bool GLRenderer::IsContextLost() {
   return (context_->getGraphicsResetStatusARB() != GL_NO_ERROR);
 }
 
+gfx::Rect GLRenderer::GetFrameDamage() {
+  gfx::Rect frame_damage = swap_buffer_rect_;
+  frame_damage.Intersect(client_->DeviceViewport());
+  int flipped_y_pos_of_rect_bottom = client_->DeviceViewport().height() -
+                                     frame_damage.y() - frame_damage.height();
+  frame_damage.set_y(flipped_y_pos_of_rect_bottom);
+  return frame_damage;
+}
+
 }  // namespace cc