Support stacktrace and objecthistogram service commands

runtime/vm/json_stream.h

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_JSON_STREAM_H_
 #define VM_JSON_STREAM_H_
 
 #include "platform/json.h"
 
 namespace dart {
@@ skipping 10 matching lines @@
   void OpenObject(const char* property_name = NULL);
   void CloseObject();
 
   void OpenArray(const char* property_name = NULL);
   void CloseArray();
 
   void PrintValueBool(bool b);
   void PrintValue(intptr_t i);
   void PrintValue(double d);
   void PrintValue(const char* s);
+  void PrintfValue(const char* format, ...) PRINTF_ATTRIBUTE(2, 3);
   void PrintValue(const Object& o, bool ref = true);
 
   void PrintPropertyBool(const char* name, bool b);
   void PrintProperty(const char* name, intptr_t i);
   void PrintProperty(const char* name, double d);
   void PrintProperty(const char* name, const char* s);
+  void PrintfProperty(const char* name, const char* format, ...)
+      PRINTF_ATTRIBUTE(3, 4);
   void PrintProperty(const char* name, const Object& o, bool ref = true);
 
  private:
   void PrintPropertyName(const char* name);
   void PrintCommaIfNeeded();
   bool NeedComma();
   intptr_t open_objects_;
   TextBuffer* buffer_;
 };
 
 }  // namespace dart
 
 #endif  // VM_JSON_STREAM_H_