Support doing CopyOutputRequests on surfaces.

cc/surfaces/surface.cc

Index: cc/surfaces/surface.cc
diff --git a/cc/surfaces/surface.cc b/cc/surfaces/surface.cc
index 8f08d63d9275e9d77d6c1e0fa912b98524272237..d58ed4cc18046fbc667d7490d011436a3cff5a86 100644
--- a/cc/surfaces/surface.cc
+++ b/cc/surfaces/surface.cc
@@ -22,6 +22,12 @@ Surface::Surface(SurfaceId id, const gfx::Size& size, SurfaceFactory* factory)
 }
 
 Surface::~Surface() {
+  for (ScopedPtrVector<CopyOutputRequest>::iterator it = copy_requests_.begin();
+       it != copy_requests_.end();
+       ++it) {
+    (*it)->SendEmptyResult();
+  }
+  copy_requests_.clear();
   if (current_frame_) {
     ReturnedResourceArray current_resources;
     TransferableResource::ReturnResources(
@@ -33,6 +39,13 @@ Surface::~Surface() {
 
 void Surface::QueueFrame(scoped_ptr<CompositorFrame> frame,
                          const base::Closure& callback) {
+  for (ScopedPtrVector<CopyOutputRequest>::iterator it = copy_requests_.begin();
+       it != copy_requests_.end();
+       ++it) {
+    (*it)->SendEmptyResult();
+  }
+  copy_requests_.clear();
+
   TakeLatencyInfo(&frame->metadata.latency_info);
   scoped_ptr<CompositorFrame> previous_frame = current_frame_.Pass();
   current_frame_ = frame.Pass();
@@ -53,8 +66,13 @@ void Surface::QueueFrame(scoped_ptr<CompositorFrame> frame,
 }
 
 void Surface::RequestCopyOfOutput(scoped_ptr<CopyOutputRequest> copy_request) {
-  // TODO(jbauman): Make this work.
-  copy_request->SendEmptyResult();
+  copy_requests_.push_back(copy_request.Pass());
+}
+
+void Surface::TakeCopyOutputRequests(
+    ScopedPtrVector<CopyOutputRequest>* copy_requests) {
+  DCHECK(copy_requests->empty());
+  copy_requests->swap(copy_requests_);
 }
 
 const CompositorFrame* Surface::GetEligibleFrame() {