Rewrite std::string("") to std::string(), Linux edition.

jingle/notifier/communicator/single_login_attempt_unittest.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 "jingle/notifier/communicator/single_login_attempt.h"
 
 #include <cstddef>
 
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 201 matching lines @@
       MakeRedirectError(redirect_server.server.host() + ":invalidport"));
   FireRedirect(redirect_error.get());
 
   EXPECT_EQ(REDIRECTED, fake_delegate_.state());
   EXPECT_TRUE(fake_delegate_.redirect_server().Equals(redirect_server));
 }
 
 // Fire an empty redirect and make sure the delegate does not get a
 // redirect.
 TEST_F(SingleLoginAttemptTest, RedirectEmpty) {
-  scoped_ptr<buzz::XmlElement> redirect_error(MakeRedirectError(""));
+  scoped_ptr<buzz::XmlElement> redirect_error(MakeRedirectError(std::string()));
   FireRedirect(redirect_error.get());
   EXPECT_EQ(IDLE, fake_delegate_.state());
 }
 
 // Fire a redirect with a missing text element and make sure the
 // delegate does not get a redirect.
 TEST_F(SingleLoginAttemptTest, RedirectMissingText) {
-  scoped_ptr<buzz::XmlElement> redirect_error(MakeRedirectError(""));
+  scoped_ptr<buzz::XmlElement> redirect_error(MakeRedirectError(std::string()));
   redirect_error->RemoveChildAfter(redirect_error->FirstChild());
   FireRedirect(redirect_error.get());
   EXPECT_EQ(IDLE, fake_delegate_.state());
 }
 
 // Fire a redirect with a missing see-other-host element and make sure
 // the delegate does not get a redirect.
 TEST_F(SingleLoginAttemptTest, RedirectMissingSeeOtherHost) {
-  scoped_ptr<buzz::XmlElement> redirect_error(MakeRedirectError(""));
+  scoped_ptr<buzz::XmlElement> redirect_error(MakeRedirectError(std::string()));
   redirect_error->RemoveChildAfter(NULL);
   FireRedirect(redirect_error.get());
   EXPECT_EQ(IDLE, fake_delegate_.state());
 }
 
 // Fire 'Unauthorized' errors and make sure the delegate gets the
 // OnCredentialsRejected() event.
 TEST_F(SingleLoginAttemptTest, CredentialsRejected) {
   attempt_.OnError(buzz::XmppEngine::ERROR_UNAUTHORIZED, 0, NULL);
   EXPECT_EQ(CREDENTIALS_REJECTED, fake_delegate_.state());
 }
 
 }  // namespace
 
 }  // namespace notifier