Allow CopyOutputRequests on all render passes of a surface

cc/surfaces/surface.h

Index: cc/surfaces/surface.h
diff --git a/cc/surfaces/surface.h b/cc/surfaces/surface.h
index 718fef4a1fd5782eaeb43a6b474d2a807ce8d302..b061cfad3f03c650f33360052f7749e151b5f5fa 100644
--- a/cc/surfaces/surface.h
+++ b/cc/surfaces/surface.h
@@ -39,8 +39,10 @@ class CC_SURFACES_EXPORT Surface {
   void QueueFrame(scoped_ptr<CompositorFrame> frame,
                   const base::Closure& draw_callback);
   void RequestCopyOfOutput(scoped_ptr<CopyOutputRequest> copy_request);
+  // Modifies copy_requests to have a ScopedPtrVector for each render pass in
+  // the current frame, containing all the copy requests from pass.
   void TakeCopyOutputRequests(
-      ScopedPtrVector<CopyOutputRequest>* copy_requests);
+      ScopedPtrVector<ScopedPtrVector<CopyOutputRequest>>* copy_requests);

[jamesr, 2014/10/15 03:21:39]

why's this a pointer to a vector of pointers of vectors of pointers?

if this is intended to be sparse, instead of passing piles of NULLs can we pass
a list of tuples of CopyOutputRequest, pass id, quad ids?  there should be 0 or
1 entry in this in the average case

   // Returns the most recent frame that is eligible to be rendered.
   const CompositorFrame* GetEligibleFrame();
 
@@ -53,13 +55,14 @@ class CC_SURFACES_EXPORT Surface {
   SurfaceFactory* factory() { return factory_; }
 
  private:
+  void ClearCopyRequests();
+
   SurfaceId surface_id_;
   gfx::Size size_;
   SurfaceFactory* factory_;
   // TODO(jamesr): Support multiple frames in flight.
   scoped_ptr<CompositorFrame> current_frame_;
   int frame_index_;
-  ScopedPtrVector<CopyOutputRequest> copy_requests_;
 
   base::Closure draw_callback_;