Add builders for tracing event's structural arguments

cc/trees/layer_tree_host_impl.h

Index: cc/trees/layer_tree_host_impl.h
diff --git a/cc/trees/layer_tree_host_impl.h b/cc/trees/layer_tree_host_impl.h
index eae28664bee6980dd0b5d5d74ea4dffebba905e6..3d2d7b0cdf0a11a03f1c726678274e5f667895dc 100644
--- a/cc/trees/layer_tree_host_impl.h
+++ b/cc/trees/layer_tree_host_impl.h
@@ -165,7 +165,7 @@ class CC_EXPORT LayerTreeHostImpl
   struct CC_EXPORT FrameData : public RenderPassSink {
     FrameData();
     virtual ~FrameData();
-    scoped_ptr<base::Value> AsValue() const;
+    void AsValueInto(base::debug::TracedValue* value) const;
 
     std::vector<gfx::Rect> occluding_screen_space_rects;
     std::vector<gfx::Rect> non_occluding_screen_space_rects;
@@ -428,9 +428,17 @@ class CC_EXPORT LayerTreeHostImpl
     return begin_impl_frame_interval_;
   }
 
-  scoped_ptr<base::Value> AsValue() const { return AsValueWithFrame(NULL); }
-  scoped_ptr<base::Value> AsValueWithFrame(FrameData* frame) const;
-  scoped_ptr<base::Value> ActivationStateAsValue() const;
+  void AsValueInto(base::debug::TracedValue* value) const {
+    return AsValueWithFrameInto(NULL, value);
+  }
+  void AsValueWithFrameInto(FrameData* frame,
+                            base::debug::TracedValue* value) const;
+  scoped_refptr<base::debug::ConvertableToTraceFormat> AsValue() const;
+  scoped_refptr<base::debug::ConvertableToTraceFormat> AsValueWithFrame(
+      FrameData* frame) const;
+  scoped_refptr<base::debug::ConvertableToTraceFormat> ActivationStateAsValue()
+      const;
+  void ActivationStateAsValueInto(base::debug::TracedValue* value) const;
 
   bool page_scale_animation_active() const { return !!page_scale_animation_; }