cc: Cleanup class/struct forward declarations

cc/trees/layer_tree_host_in_process.h

 // 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.
 
 #ifndef CC_TREES_LAYER_TREE_HOST_IN_PROCESS_H_
 #define CC_TREES_LAYER_TREE_HOST_IN_PROCESS_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 29 matching lines @@
 #include "cc/trees/layer_tree_host_client.h"
 #include "cc/trees/layer_tree_settings.h"
 #include "cc/trees/proxy.h"
 #include "cc/trees/swap_promise_manager.h"
 #include "cc/trees/target_property.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/gfx/geometry/rect.h"
 
 namespace cc {
 class MutatorEvents;
-class BeginFrameSource;
 class ClientPictureCache;
 class EnginePictureCache;
-class HeadsUpDisplayLayer;
 class ImageSerializationProcessor;
 class Layer;
 class LayerTreeHostClient;
 class LayerTreeHostImpl;
 class LayerTreeHostImplClient;
 class LayerTreeHostSingleThreadClient;
 class LayerTreeMutator;
 class MutatorHost;
 class PropertyTrees;
-class Region;
 class RenderingStatsInstrumentation;
-class ResourceProvider;
-class ResourceUpdateQueue;
 class TaskGraphRunner;
-struct PendingPageScaleAnimation;
 struct ReflectedMainFrameState;
 struct RenderingStats;
 struct ScrollAndScaleSet;
 
 class CC_EXPORT LayerTreeHostInProcess : public LayerTreeHost {
  public:
   // TODO(sad): InitParams should be a movable type so that it can be
   // std::move()d to the Create* functions.
   struct CC_EXPORT InitParams {
     LayerTreeHostClient* client = nullptr;
@@ skipping 243 matching lines @@
   // TODO(khushalsagar): Investigate removing this after SPV2, since then we
   // should get these PropertyTrees directly from blink?
   std::unique_ptr<ReflectedMainFrameState> reflected_main_frame_state_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostInProcess);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_HOST_IN_PROCESS_H_