Remove parts of //cc we aren't using

cc/trees/damage_tracker.h

Index: cc/trees/damage_tracker.h
diff --git a/cc/trees/damage_tracker.h b/cc/trees/damage_tracker.h
deleted file mode 100644
index aafbd033bcd0d0823a487e0390427920c7b7b4ce..0000000000000000000000000000000000000000
--- a/cc/trees/damage_tracker.h
+++ /dev/null
@@ -1,93 +0,0 @@
-// 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_DAMAGE_TRACKER_H_
-#define CC_TREES_DAMAGE_TRACKER_H_
-
-#include <vector>
-#include "base/memory/scoped_ptr.h"
-#include "cc/base/cc_export.h"
-#include "cc/layers/layer_lists.h"
-#include "ui/gfx/geometry/rect.h"
-
-class SkImageFilter;
-
-namespace gfx {
-class Rect;
-}
-
-namespace cc {
-
-class FilterOperations;
-class LayerImpl;
-class RenderSurfaceImpl;
-
-// Computes the region where pixels have actually changed on a
-// RenderSurfaceImpl. This region is used to scissor what is actually drawn to
-// the screen to save GPU computation and bandwidth.
-class CC_EXPORT DamageTracker {
- public:
-  static scoped_ptr<DamageTracker> Create();
-  ~DamageTracker();
-
-  void DidDrawDamagedArea() { current_damage_rect_ = gfx::Rect(); }
-  void AddDamageNextUpdate(const gfx::Rect& dmg) {
-    current_damage_rect_.Union(dmg);
-  }
-  void UpdateDamageTrackingState(
-      const LayerImplList& layer_list,
-      int target_surface_layer_id,
-      bool target_surface_property_changed_only_from_descendant,
-      const gfx::Rect& target_surface_content_rect,
-      LayerImpl* target_surface_mask_layer,
-      const FilterOperations& filters);
-
-  gfx::Rect current_damage_rect() { return current_damage_rect_; }
-
- private:
-  DamageTracker();
-
-  gfx::Rect TrackDamageFromActiveLayers(const LayerImplList& layer_list,
-                                        int target_surface_layer_id);
-  gfx::Rect TrackDamageFromSurfaceMask(LayerImpl* target_surface_mask_layer);
-  gfx::Rect TrackDamageFromLeftoverRects();
-
-  void PrepareRectHistoryForUpdate();
-
-  // These helper functions are used only in TrackDamageFromActiveLayers().
-  void ExtendDamageForLayer(LayerImpl* layer, gfx::Rect* target_damage_rect);
-  void ExtendDamageForRenderSurface(LayerImpl* layer,
-                                    gfx::Rect* target_damage_rect);
-
-  struct RectMapData {
-    RectMapData() : layer_id_(0), mailboxId_(0) {}
-    explicit RectMapData(int layer_id) : layer_id_(layer_id), mailboxId_(0) {}
-    void Update(const gfx::Rect& rect, unsigned int mailboxId) {
-      mailboxId_ = mailboxId;
-      rect_ = rect;
-    }
-
-    bool operator < (const RectMapData& other) const {
-      return layer_id_ < other.layer_id_;
-    }
-
-    int layer_id_;
-    unsigned int mailboxId_;
-    gfx::Rect rect_;
-  };
-  typedef std::vector<RectMapData> SortedRectMap;
-
-  RectMapData& RectDataForLayer(int layer_id, bool* layer_is_new);
-
-  SortedRectMap rect_history_;
-
-  unsigned int mailboxId_;
-  gfx::Rect current_damage_rect_;
-
-  DISALLOW_COPY_AND_ASSIGN(DamageTracker);
-};
-
-}  // namespace cc
-
-#endif  // CC_TREES_DAMAGE_TRACKER_H_