Refactor MutatorHostClient from LayerTreeHost to LayerTree.

cc/debug/invalidation_benchmark.h

Index: cc/debug/invalidation_benchmark.h
diff --git a/cc/debug/invalidation_benchmark.h b/cc/debug/invalidation_benchmark.h
index 668a7c948e9bc075a965101f21955a13746f1ec3..d30ac3f1e1809eb7b2f3d60249fe3f986763e629 100644
--- a/cc/debug/invalidation_benchmark.h
+++ b/cc/debug/invalidation_benchmark.h
@@ -13,7 +13,7 @@
 
 namespace cc {
 
-class LayerTreeHost;
+class LayerTree;
 class Layer;
 // NOTE: this benchmark will not measure or return any results, it will simply
 // invalidate a certain area of each layer every frame. It is intended to be
@@ -26,7 +26,7 @@ class CC_EXPORT InvalidationBenchmark : public MicroBenchmark {
   ~InvalidationBenchmark() override;
 
   // Implements MicroBenchmark interface.
-  void DidUpdateLayers(LayerTreeHost* host) override;
+  void DidUpdateLayers(LayerTree* layer_tree) override;
   void RunOnLayer(PictureLayer* layer) override;
   bool ProcessMessage(std::unique_ptr<base::Value> value) override;