cc: Add a helper function for transforming rects between surface spaces

cc/trees/layer_tree_host_common_unittest.cc

 // Copyright 2011 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/trees/layer_tree_host_common.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <memory>
@@ skipping 4020 matching lines @@
   clip_child->SetDrawsContent(true);
   clip_child->test_properties()->clip_parent = clip_parent;
 
   render_surface2->SetBounds(gfx::Size(60, 60));
   render_surface2->SetDrawsContent(true);
   render_surface2->test_properties()->force_render_surface = true;
 
   clip_parent->SetMasksToBounds(true);
   render_surface1->SetMasksToBounds(true);
 
-  ExecuteCalculateDrawProperties(root);
+  float device_scale_factor = 1.f;
+  ExecuteCalculateDrawProperties(root, device_scale_factor);
   EXPECT_EQ(gfx::Rect(50, 50),
             render_surface2->GetRenderSurface()->clip_rect());
+  device_scale_factor = 2.f;
+  ExecuteCalculateDrawProperties(root, device_scale_factor);
+  EXPECT_EQ(gfx::Rect(100, 100),
+            render_surface2->GetRenderSurface()->clip_rect());
 }
 
 TEST_F(LayerTreeHostCommonTest, RenderSurfaceContentRectWhenLayerNotDrawn) {
   // Test that only drawn layers contribute to render surface content rect.
   LayerImpl* root = root_layer_for_testing();
   LayerImpl* surface = AddChildToRoot<LayerImpl>();
   LayerImpl* test_layer = AddChild<LayerImpl>(surface);
 
   root->SetBounds(gfx::Size(200, 200));
   surface->SetBounds(gfx::Size(100, 100));
@@ skipping 6707 matching lines @@
   EXPECT_EQ(scroll_child6.id, grand_child10->scroll_tree_index());
   EXPECT_EQ(scroll_root1.id, parent3->scroll_tree_index());
   EXPECT_EQ(scroll_child7.id, child8->scroll_tree_index());
   EXPECT_EQ(scroll_root1.id, parent4->scroll_tree_index());
   EXPECT_EQ(scroll_root1.id, child9->scroll_tree_index());
   EXPECT_EQ(scroll_root1.id, grand_child12->scroll_tree_index());
 }
 
 }  // namespace
 }  // namespace cc