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 7b3c3fdfb95105cd8e05c444a0ff5d91a22f86bf..821028fa64595c087bf1cbc21aa4e4ccb12729ff 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;
@@ -434,9 +434,17 @@ 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_; }