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

chrome/test/webdriver/webdriver_session_manager.cc

 // Copyright (c) 2011 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/test/webdriver/webdriver_session_manager.h"
 
 #include "chrome/test/webdriver/webdriver_session.h"
 
 namespace webdriver {
 
@@ skipping 31 matching lines @@
 }
 
 void SessionManager::set_url_base(const std::string& url_base) {
   url_base_ = url_base;
 }
 
 std::string SessionManager::url_base() const {
   return url_base_;
 }
 
-SessionManager::SessionManager() : port_(""), url_base_("") {}
+SessionManager::SessionManager() {}
 
 SessionManager::~SessionManager() {}
 
 // static
 SessionManager* SessionManager::GetInstance() {
   return Singleton<SessionManager>::get();
 }
 
 }  // namespace webdriver