Revert of cc: Move data to LayerTree from LayerTreeHost.

cc/trees/layer_tree_host_unittest_proxy.cc

Index: cc/trees/layer_tree_host_unittest_proxy.cc
diff --git a/cc/trees/layer_tree_host_unittest_proxy.cc b/cc/trees/layer_tree_host_unittest_proxy.cc
index 30fed5a7ff15ceeacef9ffc46cacae00dd3d2e77..189bcae23714888d4a2a2a85ac854cacc5ad3642 100644
--- a/cc/trees/layer_tree_host_unittest_proxy.cc
+++ b/cc/trees/layer_tree_host_unittest_proxy.cc
@@ -16,7 +16,7 @@
  protected:
   void SetupTree() override {
     update_check_layer_ = FakePictureLayer::Create(&client_);
-    layer_tree()->SetRootLayer(update_check_layer_);
+    layer_tree_host()->SetRootLayer(update_check_layer_);
     LayerTreeTest::SetupTree();
     client_.set_bounds(update_check_layer_->bounds());
   }