Enqueuing new frames in a Surface should cause Displays to reaggregate it

cc/surfaces/surface.cc

Index: cc/surfaces/surface.cc
diff --git a/cc/surfaces/surface.cc b/cc/surfaces/surface.cc
index 55c7392249806d90cb8f81c1b6d030e3043b8632..c7e44a6e2ceea57667d601b96d617ada8beb0272 100644
--- a/cc/surfaces/surface.cc
+++ b/cc/surfaces/surface.cc
@@ -5,6 +5,7 @@
 #include "cc/surfaces/surface.h"
 
 #include "cc/output/compositor_frame.h"
+#include "cc/surfaces/display.h"
 #include "cc/surfaces/surface_factory.h"
 
 namespace cc {
@@ -14,6 +15,11 @@ Surface::Surface(SurfaceId id, const gfx::Size& size, SurfaceFactory* factory)
 }
 
 Surface::~Surface() {
+  for (std::set<Display*>::iterator it = containing_displays_.begin();

[jamesr, 2014/08/07 21:04:06]

if you used IDs then you wouldn't need to do this - the SurfaceManager's
id->surface mapping is your weak pointer

+       it != containing_displays_.end();
+       ++it) {
+    (*it)->contained_surfaces().erase(this);
+  }
   if (current_frame_) {
     ReturnedResourceArray current_resources;
     TransferableResource::ReturnResources(
@@ -36,6 +42,11 @@ void Surface::QueueFrame(scoped_ptr<CompositorFrame> frame) {
         &previous_resources);
     factory_->UnrefResources(previous_resources);
   }
+  for (std::set<Display*>::iterator it = containing_displays_.begin();
+       it != containing_displays_.end();
+       ++it) {
+    (*it)->Draw();

[jamesr, 2014/08/07 21:04:06]

i think the service should be keeping track of this, not the individual
surfaces. i.e. the thing that's routing queue frame calls to Surface instances
can say 'ok, for this surface ID is there any display that needs to re-aggregate
as a result of this'?

also saying that a new frame needs a draw isn't entirely correct.  When
receiving a new frame, we need to re-aggregate and then look at the damage to
see if that requires us to draw or not. in many cases we won't actually have to
draw anything new

+  }
 }
 
 const CompositorFrame* Surface::GetEligibleFrame() {