Don't delete CopyOutputRequests when queueing a new Surface frame.

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 <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 146 matching lines @@
   DCHECK(pending_frame_);
   ActivateFrame(std::move(pending_frame_.value()));
   pending_frame_.reset();
 }
 
 // A frame is activated if all its Surface ID dependences are active or a
 // deadline has hit and the frame was forcibly activated by the display
 // compositor.
 void Surface::ActivateFrame(CompositorFrame frame) {
   DCHECK(factory_);
+
+  // Save root pass copy requests.
+  std::vector<std::unique_ptr<CopyOutputRequest>> old_copy_requests;
+  if (active_frame_ && !active_frame_->render_pass_list.empty()) {
+    std::swap(old_copy_requests,
+              active_frame_->render_pass_list.back()->copy_requests);
+  }
+
   ClearCopyRequests();
 
   TakeLatencyInfo(&frame.metadata.latency_info);
 
   base::Optional<CompositorFrame> previous_frame = std::move(active_frame_);
   active_frame_ = std::move(frame);
 
+  for (auto& copy_request : old_copy_requests)
+    RequestCopyOfOutput(std::move(copy_request));
+
   // Empty frames shouldn't be drawn and shouldn't contribute damage, so don't
   // increment frame index for them.
   if (!active_frame_->render_pass_list.empty())
     ++frame_index_;
 
   previous_frame_surface_id_ = surface_id();
 
   if (previous_frame)
     UnrefFrameResources(*previous_frame);
 
@@ skipping 130 matching lines @@
 void Surface::ClearCopyRequests() {
   if (active_frame_) {
     for (const auto& render_pass : active_frame_->render_pass_list) {
       for (const auto& copy_request : render_pass->copy_requests)
         copy_request->SendEmptyResult();
     }
   }
 }
 
 }  // namespace cc