Plumb damage rect to browser compositor.

content/browser/renderer_host/render_widget_host_view_aura.cc

Index: content/browser/renderer_host/render_widget_host_view_aura.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.cc b/content/browser/renderer_host/render_widget_host_view_aura.cc
index 997886291df8ce2226855871d58e5633dc740e03..65768a48d7c6d20bdce329adc250f24704b4cdb7 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.cc
+++ b/content/browser/renderer_host/render_widget_host_view_aura.cc
@@ -334,8 +334,9 @@ void RenderWidgetHostViewAura::AcceleratedSurfacePostSubBuffer(
     const GpuHostMsg_AcceleratedSurfacePostSubBuffer_Params& params,
     int gpu_host_id) {
 #if defined(UI_COMPOSITOR_IMAGE_TRANSPORT)
-  window_->layer()->SetExternalTexture(
-      accelerated_surface_containers_[params.surface_id]->GetTexture());
+  scoped_refptr<AcceleratedSurfaceContainerLinux> container =
+      accelerated_surface_containers_[params.surface_id];
+    window_->layer()->SetExternalTexture(container->GetTexture());
   glFlush();
 
   if (!window_->layer()->GetCompositor()) {
@@ -343,9 +344,16 @@ void RenderWidgetHostViewAura::AcceleratedSurfacePostSubBuffer(
     // Must still send the ACK
     RenderWidgetHost::AcknowledgePostSubBuffer(params.route_id, gpu_host_id);
   } else {
-    // TODO(backer): Plumb the damage rect to the ui compositor so that we
-    // can do a partial swap to display.
+#if defined(USE_WEBKIT_COMPOSITOR)
+    // Co-ords come in GL co-ord space. Need to convert to layer space.
+    window_->layer()->SchedulePaint(gfx::Rect(
+       params.x,
+       container->GetSize().height() - params.y - params.height,

[apatrick_chromium, 2011/12/06 01:10:30]

It looks like a lot of this function is reaching into window_->layer() and that
it could perhaps move there. I don't really know what window_->layer() is though
:)

[jonathan.backer, 2011/12/06 01:25:12]

I'm asking for the layer for a paint in it's co-ordinate system. It may be
possible to combine the two calls (SetExternalTexture and SchedulePaint), but
they have independent uses.

+       params.width,
+       params.height));
+#else
     window_->layer()->ScheduleDraw();
+#endif
 
     // Add sending an ACK to the list of things to do OnCompositingEnded
     on_compositing_ended_callbacks_.push_back(