Adding PrintTo of ObjectPath for gtest.

dbus/object_path.cc

 // Copyright (c) 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.
 
 #include "dbus/object_path.h"
 
+#include <ostream>
+
 #include "dbus/string_util.h"
 
 namespace dbus {
 
 bool ObjectPath::IsValid() const {
   return IsValidObjectPath(value_);
 }
 
 bool ObjectPath::operator<(const ObjectPath& that) const {
   return value_ < that.value_;
 }
 
 bool ObjectPath::operator==(const ObjectPath& that) const {
   return value_ == that.value_;
 }
 
 bool ObjectPath::operator!=(const ObjectPath& that) const {
   return value_ != that.value_;
 }
 
+void PrintTo(const ObjectPath& path, std::ostream* out) {
+  *out << path.value();
+}
+
 } // namespace dbus