cc: Remove all traces of SkPicture cloning.

cc/resources/picture_pile_impl.h

 // 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.
 
 #ifndef CC_RESOURCES_PICTURE_PILE_IMPL_H_
 #define CC_RESOURCES_PICTURE_PILE_IMPL_H_
 
 #include <list>
 #include <map>
 #include <set>
 #include <vector>
 
 #include "base/time/time.h"
 #include "cc/base/cc_export.h"
 #include "cc/debug/rendering_stats_instrumentation.h"
 #include "cc/resources/picture_pile_base.h"
 #include "skia/ext/analysis_canvas.h"
 #include "skia/ext/refptr.h"
 #include "third_party/skia/include/core/SkPicture.h"
 
 namespace cc {
 
 class CC_EXPORT PicturePileImpl : public PicturePileBase {
  public:
   static scoped_refptr<PicturePileImpl> Create();
   static scoped_refptr<PicturePileImpl> CreateFromOther(
       const PicturePileBase* other);
 
-  // Get paint-safe version of this picture for a specific thread.
-  PicturePileImpl* GetCloneForDrawingOnThread(unsigned thread_index) const;
-
-  // Raster a subrect of this PicturePileImpl into the given canvas.
-  // It's only safe to call paint on a cloned version.  It is assumed
-  // that contents_scale has already been applied to this canvas.
+  // Raster a subrect of this PicturePileImpl into the given canvas. It is
+  // assumed that contents_scale has already been applied to this canvas.
   // Writes the total number of pixels rasterized and the time spent
-  // rasterizing to the stats if the respective pointer is not
-  // NULL. When slow-down-raster-scale-factor is set to a value
-  // greater than 1, the reported rasterize time is the minimum
-  // measured value over all runs.
+  // rasterizing to the stats if the respective pointer is not NULL. When
+  // slow-down-raster-scale-factor is set to a value greater than 1, the
+  // reported rasterize time is the minimum measured value over all runs.
   void RasterDirect(
       SkCanvas* canvas,
       const gfx::Rect& canvas_rect,
       float contents_scale,
       RenderingStatsInstrumentation* rendering_stats_instrumentation);
 
   // Similar to the above RasterDirect method, but this is a convenience method
   // for when it is known that the raster is going to an intermediate bitmap
   // that itself will then be blended and thus that a canvas clear is required.
   // Note that this function may write outside the canvas_rect.
   void RasterToBitmap(
       SkCanvas* canvas,
       const gfx::Rect& canvas_rect,
       float contents_scale,
-      RenderingStatsInstrumentation* stats_instrumentation);
+      RenderingStatsInstrumentation* stats_instrumentation) const;
 
   // Called when analyzing a tile. We can use AnalysisCanvas as
   // SkDrawPictureCallback, which allows us to early out from analysis.
   void RasterForAnalysis(
       skia::AnalysisCanvas* canvas,
       const gfx::Rect& canvas_rect,
       float contents_scale,
-      RenderingStatsInstrumentation* stats_instrumentation);
+      RenderingStatsInstrumentation* stats_instrumentation) const;
 
   skia::RefPtr<SkPicture> GetFlattenedPicture();
 
   struct CC_EXPORT Analysis {
     Analysis();
     ~Analysis();
 
     bool is_solid_color;
     SkColor solid_color;
   };
 
   void AnalyzeInRect(const gfx::Rect& content_rect,
                      float contents_scale,
-                     Analysis* analysis);
+                     Analysis* analysis) const;
 
-  void AnalyzeInRect(const gfx::Rect& content_rect,
-                     float contents_scale,
-                     Analysis* analysis,
-                     RenderingStatsInstrumentation* stats_instrumentation);
+  void AnalyzeInRect(
+      const gfx::Rect& content_rect,
+      float contents_scale,
+      Analysis* analysis,
+      RenderingStatsInstrumentation* stats_instrumentation) const;
 
   class CC_EXPORT PixelRefIterator {
    public:
     PixelRefIterator(const gfx::Rect& content_rect,
                      float contents_scale,
                      const PicturePileImpl* picture_pile);
     ~PixelRefIterator();
 
     SkPixelRef* operator->() const { return *pixel_ref_iterator_; }
     SkPixelRef* operator*() const { return *pixel_ref_iterator_; }
@@ skipping 14 matching lines @@
 
  protected:
   friend class PicturePile;
   friend class PixelRefIterator;
 
   PicturePileImpl();
   explicit PicturePileImpl(const PicturePileBase* other);
   virtual ~PicturePileImpl();
 
  private:
-  class ClonesForDrawing {
-   public:
-    ClonesForDrawing(const PicturePileImpl* pile, int num_threads);
-    ~ClonesForDrawing();
+  typedef std::map<const Picture*, Region> PictureRegionMap;
 
-    typedef std::vector<scoped_refptr<PicturePileImpl> > PicturePileVector;
-    PicturePileVector clones_;
-  };
-
-  static scoped_refptr<PicturePileImpl> CreateCloneForDrawing(
-      const PicturePileImpl* other, unsigned thread_index);
-
-  PicturePileImpl(const PicturePileImpl* other, unsigned thread_index);
-
- private:
-  typedef std::map<Picture*, Region> PictureRegionMap;
   void CoalesceRasters(const gfx::Rect& canvas_rect,
                        const gfx::Rect& content_rect,
                        float contents_scale,
-                       PictureRegionMap* result);
+                       PictureRegionMap* result) const;
 
   void RasterCommon(
       SkCanvas* canvas,
       SkDrawPictureCallback* callback,
       const gfx::Rect& canvas_rect,
       float contents_scale,
       RenderingStatsInstrumentation* rendering_stats_instrumentation,
-      bool is_analysis);
-
-  // Once instantiated, |clones_for_drawing_| can't be modified.  This
-  // guarantees thread-safe access during the life time of a PicturePileImpl
-  // instance.  This member variable must be last so that other member
-  // variables have already been initialized and can be clonable.
-  const ClonesForDrawing clones_for_drawing_;
+      bool is_analysis) const;
 
   DISALLOW_COPY_AND_ASSIGN(PicturePileImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_PICTURE_PILE_IMPL_H_