Fix unused variables errors in cc/.

cc/trees/layer_tree_host.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/trees/layer_tree_host.h"
 
 #include <algorithm>
 #include <stack>
 #include <string>
 
@@ skipping 106 matching lines @@
       next_commit_forces_redraw_(false),
       shared_bitmap_manager_(params->shared_bitmap_manager),
       gpu_memory_buffer_manager_(params->gpu_memory_buffer_manager),
       task_graph_runner_(params->task_graph_runner),
       surface_id_namespace_(0u),
       next_surface_sequence_(1u) {
   DCHECK(task_graph_runner_);
 
   if (settings_.accelerated_animation_enabled) {
     if (settings_.use_compositor_animation_timelines) {
-      animation_host_ = AnimationHost::Create(ThreadInstance::MAIN);
+      animation_host_ = AnimationHost::Create();
       animation_host_->SetMutatorHostClient(this);
     } else {
       animation_registrar_ = AnimationRegistrar::Create();
     }
   }
 
   rendering_stats_instrumentation_->set_record_rendering_stats(
       debug_state_.RecordRenderingStats());
 }
 
@@ skipping 1062 matching lines @@
   return animation_host_ ? animation_host_->HasAnyAnimation(layer->id())
                          : false;
 }
 
 bool LayerTreeHost::HasActiveAnimation(const Layer* layer) const {
   return animation_host_ ? animation_host_->HasActiveAnimation(layer->id())
                          : false;
 }
 
 }  // namespace cc