Avoid copying ChildToParentMap in SurfaceAggregator.

cc/surfaces/surface_aggregator.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_aggregator.h"
 
 #include <map>
 
 #include "base/bind.h"
 #include "base/containers/hash_tables.h"
@@ skipping 151 matching lines @@
 
   int child_id = ChildIdForSurface(surface);
   if (surface->factory())
     surface->factory()->RefResources(frame_data->resource_list);
   provider_->ReceiveFromChild(child_id, frame_data->resource_list);
 
   typedef ResourceProvider::ResourceIdArray IdArray;
   IdArray referenced_resources;
 
   bool invalid_frame = false;
-  DrawQuad::ResourceIteratorCallback remap = base::Bind(
-      &ValidateResourceHelper, &invalid_frame,
-      provider_->GetChildToParentMap(child_id), &referenced_resources);
+  DrawQuad::ResourceIteratorCallback remap =
+      base::Bind(&ValidateResourceHelper, &invalid_frame,
+                 base::ConstRef(provider_->GetChildToParentMap(child_id)),
+                 &referenced_resources);
   for (const auto& render_pass : frame_data->render_pass_list) {
     for (const auto& quad : render_pass->quad_list)
       quad->IterateResources(remap);
   }
 
   if (!invalid_frame)
     provider_->DeclareUsedResourcesFromChild(child_id, referenced_resources);
 
   return invalid_frame;
 }
@@ skipping 42 matching lines @@
       request.second->SendEmptyResult();
       delete request.second;
     }
     return;
   }
 
   SurfaceSet::iterator it = referenced_surfaces_.insert(surface_id).first;
   DrawQuad::ResourceIteratorCallback remap;
   if (provider_) {
     int child_id = ChildIdForSurface(surface);
-    remap = base::Bind(&ResourceRemapHelper,
-                       provider_->GetChildToParentMap(child_id));
+    remap =
+        base::Bind(&ResourceRemapHelper,
+                   base::ConstRef(provider_->GetChildToParentMap(child_id)));
   }
 
   bool merge_pass = surface_quad->opacity() == 1.f && copy_requests.empty();
 
   gfx::Rect surface_damage = DamageRectForSurface(
       surface, *render_pass_list.back(), surface_quad->visible_rect);
   const RenderPassList& referenced_passes = render_pass_list;
   size_t passes_to_copy =
       merge_pass ? referenced_passes.size() - 1 : referenced_passes.size();
   for (size_t j = 0; j < passes_to_copy; ++j) {
@@ skipping 175 matching lines @@
 
   const RenderPassList& source_pass_list = frame_data->render_pass_list;
   bool invalid_frame = ValidateResources(surface, frame_data);
   DCHECK(!invalid_frame);
   if (invalid_frame)
     return;
 
   DrawQuad::ResourceIteratorCallback remap;
   if (provider_) {
     int child_id = ChildIdForSurface(surface);
-    remap = base::Bind(&ResourceRemapHelper,
-                       provider_->GetChildToParentMap(child_id));
+    remap =
+        base::Bind(&ResourceRemapHelper,
+                   base::ConstRef(provider_->GetChildToParentMap(child_id)));
   }
 
   for (size_t i = 0; i < source_pass_list.size(); ++i) {
     const RenderPass& source = *source_pass_list[i];
 
     size_t sqs_size = source.shared_quad_state_list.size();
     size_t dq_size = source.quad_list.size();
     scoped_ptr<RenderPass> copy_pass(RenderPass::Create(sqs_size, dq_size));
 
     MoveMatchingRequests(source.id, &copy_requests, &copy_pass->copy_requests);
@@ skipping 83 matching lines @@
 void SurfaceAggregator::ReleaseResources(SurfaceId surface_id) {
   SurfaceToResourceChildIdMap::iterator it =
       surface_id_to_resource_child_id_.find(surface_id);
   if (it != surface_id_to_resource_child_id_.end()) {
     provider_->DestroyChild(it->second);
     surface_id_to_resource_child_id_.erase(it);
   }
 }
 
 }  // namespace cc