cc: Merge LayerTree into the LayerTreeHost.

cc/trees/layer_tree_host_pixeltest_scrollbars.cc

 // Copyright 2016 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 <stddef.h>
 
 #include "base/memory/ptr_util.h"
 #include "build/build_config.h"
 #include "cc/input/scrollbar.h"
 #include "cc/layers/painted_scrollbar_layer.h"
 #include "cc/layers/solid_color_layer.h"
 #include "cc/test/layer_tree_pixel_test.h"
 #include "cc/test/test_in_process_context_provider.h"
 #include "gpu/command_buffer/client/gles2_interface.h"
 
 #if !defined(OS_ANDROID)
 
 namespace cc {
 namespace {
 
 class LayerTreeHostScrollbarsPixelTest : public LayerTreePixelTest {
  protected:
   LayerTreeHostScrollbarsPixelTest() = default;
 
   void InitializeSettings(LayerTreeSettings* settings) override {
     settings->layer_transforms_should_scale_layer_contents = true;
   }
 
   void SetupTree() override {
-    layer_tree_host()->GetLayerTree()->SetDeviceScaleFactor(
-        device_scale_factor_);
+    layer_tree_host()->SetDeviceScaleFactor(device_scale_factor_);
     LayerTreePixelTest::SetupTree();
   }
 
   float device_scale_factor_ = 1.f;
 };
 
 class PaintedScrollbar : public Scrollbar {
  public:
   ~PaintedScrollbar() override = default;
 
@@ skipping 122 matching lines @@
   layer->SetTransform(scale_transform);
 
   RunPixelTest(PIXEL_TEST_GL, background,
                base::FilePath(FILE_PATH_LITERAL("spiral_64_scale.png")));
 }
 
 }  // namespace
 }  // namespace cc
 
 #endif  // OS_ANDROID