Fix compiling on gcc-4.6....

chrome/browser/prefs/session_startup_pref_unittest.cc

 // Copyright (c) 2010 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 "chrome/browser/prefs/session_startup_pref.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/test/testing_pref_service.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 31 matching lines @@
   url_pref_list2->Set(1, Value::CreateStringValue("chromium.org"));
   url_pref_list2->Set(2, Value::CreateStringValue("chromium.org"));
   pref_service_->SetManagedPref(prefs::kURLsToRestoreOnStartup,
                                 url_pref_list2);
 
   SessionStartupPref result =
       SessionStartupPref::GetStartupPref(pref_service_.get());
   EXPECT_EQ(3u, result.urls.size());
 
   SessionStartupPref override_test =
-      SessionStartupPref::SessionStartupPref(SessionStartupPref::URLS);
+      SessionStartupPref(SessionStartupPref::URLS);
   override_test.urls.push_back(GURL("dev.chromium.org"));
   SessionStartupPref::SetStartupPref(pref_service_.get(), override_test);
 
   result = SessionStartupPref::GetStartupPref(pref_service_.get());
   EXPECT_EQ(3u, result.urls.size());
 }