cc: Clean up root_layer code in LTI

cc/test/layer_test_common.cc

 // Copyright 2012 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_test_common.h"
 
 #include <stddef.h>
 
 #include "cc/animation/animation_host.h"
 #include "cc/animation/animation_id_provider.h"
@@ skipping 108 matching lines @@
     : LayerImplTest(LayerTreeSettingsForTesting()) {}
 
 LayerTestCommon::LayerImplTest::LayerImplTest(const LayerTreeSettings& settings)
     : client_(FakeLayerTreeHostClient::DIRECT_3D),
       output_surface_(FakeOutputSurface::Create3d()),
       host_(FakeLayerTreeHost::Create(&client_, &task_graph_runner_, settings)),
       render_pass_(RenderPass::Create()),
       layer_impl_id_(2) {
   std::unique_ptr<LayerImpl> root =
       LayerImpl::Create(host_->host_impl()->active_tree(), 1);
-  host_->host_impl()->active_tree()->SetRootLayer(std::move(root));
-  root_layer()->SetHasRenderSurface(true);
+  host_->host_impl()->active_tree()->SetRootLayerForTesting(std::move(root));
+  root_layer_for_testing()->SetHasRenderSurface(true);
   host_->host_impl()->SetVisible(true);
   host_->host_impl()->InitializeRenderer(output_surface_.get());
 
   const int timeline_id = AnimationIdProvider::NextTimelineId();
   timeline_ = AnimationTimeline::Create(timeline_id);
   host_->animation_host()->AddAnimationTimeline(timeline_);
   // Create impl-side instance.
   host_->animation_host()->PushPropertiesTo(
       host_->host_impl()->animation_host());
   timeline_impl_ =
       host_->host_impl()->animation_host()->GetTimelineById(timeline_id);
 }
 
 LayerTestCommon::LayerImplTest::~LayerImplTest() {
   host_->animation_host()->RemoveAnimationTimeline(timeline_);
   timeline_ = nullptr;
 }
 
 void LayerTestCommon::LayerImplTest::CalcDrawProps(
     const gfx::Size& viewport_size) {
   LayerImplList layer_list;
   LayerTreeHostCommon::CalcDrawPropsImplInputsForTesting inputs(
-      root_layer(), viewport_size, &layer_list);
+      root_layer_for_testing(), viewport_size, &layer_list);
   LayerTreeHostCommon::CalculateDrawPropertiesForTesting(&inputs);
 }
 
 void LayerTestCommon::LayerImplTest::AppendQuadsWithOcclusion(
     LayerImpl* layer_impl,
     const gfx::Rect& occluded) {
   AppendQuadsData data;
 
   render_pass_->quad_list.clear();
   render_pass_->shared_quad_state_list.clear();
@@ skipping 36 matching lines @@
   surface_impl->AppendQuads(
       render_pass_.get(), gfx::Transform(),
       Occlusion(gfx::Transform(), SimpleEnclosedRegion(occluded),
                 SimpleEnclosedRegion()),
       SK_ColorBLACK, 1.f, nullptr, &data, RenderPassId(1, 1));
 }
 
 void EmptyCopyOutputCallback(std::unique_ptr<CopyOutputResult> result) {}
 
 void LayerTestCommon::LayerImplTest::RequestCopyOfOutput() {
-  root_layer()->test_properties()->copy_requests.push_back(
+  root_layer_for_testing()->test_properties()->copy_requests.push_back(
       CopyOutputRequest::CreateRequest(base::Bind(&EmptyCopyOutputCallback)));
 }
 
 }  // namespace cc