Add builders for tracing event's structural arguments

cc/resources/picture_layer_tiling_set.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_LAYER_TILING_SET_H_
 #define CC_RESOURCES_PICTURE_LAYER_TILING_SET_H_
 
 #include "cc/base/region.h"
 #include "cc/base/scoped_ptr_vector.h"
 #include "cc/resources/picture_layer_tiling.h"
 #include "ui/gfx/size.h"
 
+namespace base {
+namespace debug {
+class TracedValue;
+}
+}
+
 namespace cc {
 
 class CC_EXPORT PictureLayerTilingSet {
  public:
   PictureLayerTilingSet(PictureLayerTilingClient* client,
                         const gfx::Size& layer_bounds);
   ~PictureLayerTilingSet();
 
   void SetClient(PictureLayerTilingClient* client);
   const PictureLayerTilingClient* client() const { return client_; }
@@ skipping 71 matching lines @@
     float ideal_contents_scale_;
     PictureLayerTiling::CoverageIterator tiling_iter_;
     int current_tiling_;
     int ideal_tiling_;
 
     Region current_region_;
     Region missing_region_;
     Region::Iterator region_iter_;
   };
 
-  scoped_ptr<base::Value> AsValue() const;
+  void AsValueInto(base::debug::TracedValue* array) const;
   size_t GPUMemoryUsageInBytes() const;
 
  private:
   PictureLayerTilingClient* client_;
   gfx::Size layer_bounds_;
   ScopedPtrVector<PictureLayerTiling> tilings_;
 
   friend class Iterator;
   DISALLOW_COPY_AND_ASSIGN(PictureLayerTilingSet);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_PICTURE_LAYER_TILING_SET_H_