cc: Add an integration test for what scale we draw with after pinching

cc/test/layer_tree_test.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/test/layer_tree_test.h"
 
 #include "base/command_line.h"
 #include "cc/animation/animation.h"
 #include "cc/animation/animation_registrar.h"
 #include "cc/animation/layer_animation_controller.h"
@@ skipping 238 matching lines @@
         break;
       }
     }
     test_hooks_->UpdateAnimationState(this, has_unfinished_animation);
   }
 
   base::TimeDelta LowFrequencyAnimationInterval() const override {
     return test_hooks_->LowFrequencyAnimationInterval();
   }
 
+  void NotifyTileStateChanged(const Tile* tile) override {
+    LayerTreeHostImpl::NotifyTileStateChanged(tile);
+    test_hooks_->NotifyTileStateChangedOnThread(this, tile);
+  }
+
  private:
   TestHooks* test_hooks_;
   bool block_notify_ready_to_activate_for_testing_;
   bool notify_ready_to_activate_was_blocked_;
 };
 
 // Implementation of LayerTreeHost callback interface.
 class LayerTreeHostClientForTesting : public LayerTreeHostClient,
                                       public LayerTreeHostSingleThreadClient {
  public:
@@ skipping 446 matching lines @@
   return -1;
 }
 
 void LayerTreeTest::DestroyLayerTreeHost() {
   if (layer_tree_host_ && layer_tree_host_->root_layer())
     layer_tree_host_->root_layer()->SetLayerTreeHost(NULL);
   layer_tree_host_ = nullptr;
 }
 
 }  // namespace cc