Support doing CopyOutputRequests on surfaces.

cc/surfaces/surface.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/surfaces/surface.h"
 
 #include "cc/output/compositor_frame.h"
 #include "cc/output/copy_output_request.h"
 #include "cc/surfaces/surface_factory.h"
 
 namespace cc {
 
 // The frame index starts at 2 so that empty frames will be treated as
 // completely damaged the first time they're drawn from.
 static const int kFrameIndexStart = 2;
 
 Surface::Surface(SurfaceId id, const gfx::Size& size, SurfaceFactory* factory)
     : surface_id_(id),
       size_(size),
       factory_(factory),
       frame_index_(kFrameIndexStart) {
 }
 
 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(
         current_frame_->delegated_frame_data->resource_list,
         &current_resources);
     factory_->UnrefResources(current_resources);
   }
 }
 
 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();
   factory_->ReceiveFromChild(
       current_frame_->delegated_frame_data->resource_list);
   ++frame_index_;
 
   if (previous_frame) {
     ReturnedResourceArray previous_resources;
     TransferableResource::ReturnResources(
         previous_frame->delegated_frame_data->resource_list,
         &previous_resources);
     factory_->UnrefResources(previous_resources);
   }
   if (!draw_callback_.is_null())
     draw_callback_.Run();
   draw_callback_ = callback;
 }
 
 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() {
   return current_frame_.get();
 }
 
 void Surface::TakeLatencyInfo(std::vector<ui::LatencyInfo>* latency_info) {
   if (!current_frame_)
     return;
   if (latency_info->empty()) {
     current_frame_->metadata.latency_info.swap(*latency_info);
     return;
   }
   std::copy(current_frame_->metadata.latency_info.begin(),
             current_frame_->metadata.latency_info.end(),
             std::back_inserter(*latency_info));
   current_frame_->metadata.latency_info.clear();
 }
 
 void Surface::RunDrawCallbacks() {
   if (!draw_callback_.is_null()) {
     base::Closure callback = draw_callback_;
     draw_callback_ = base::Closure();
     callback.Run();
   }
 }
 
 }  // namespace cc