Add builders for tracing event's structural arguments

cc/output/filter_operations.h

Index: cc/output/filter_operations.h
diff --git a/cc/output/filter_operations.h b/cc/output/filter_operations.h
index 66f586573ba19049a36ff476d382134d9683143b..a8c206eacd1b0593cfc3f4400420d9f3ae63c4e0 100644
--- a/cc/output/filter_operations.h
+++ b/cc/output/filter_operations.h
@@ -12,6 +12,9 @@
 #include "cc/output/filter_operation.h"
 
 namespace base {
+namespace debug {
+class TracedValue;
+}
 class Value;
 }
 
@@ -67,8 +70,7 @@ class CC_EXPORT FilterOperations {
   // a copy of this.
   FilterOperations Blend(const FilterOperations& from, double progress) const;
 
-
-  scoped_ptr<base::Value> AsValue() const;
+  void AsValueInto(base::debug::TracedValue* value) const;
 
  private:
   std::vector<FilterOperation> operations_;