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

chrome/test/chromedriver/chromedriver.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 "chrome/test/chromedriver/chromedriver.h"
 
 #include "base/json/json_reader.h"
 #include "base/json/json_writer.h"
 #include "base/lazy_instance.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 18 matching lines @@
   response_dict.Set("value", value->DeepCopy());
   response_dict.SetString("sessionId", session_id);
   std::string json;
   base::JSONWriter::Write(&response_dict, response);
 }
 
 void SetError(const std::string& error_msg,
               std::string* response) {
   base::DictionaryValue value;
   value.SetString("message", error_msg);
-  SetResponse(kUnknownError, &value, "", response);
+  SetResponse(kUnknownError, &value, std::string(), response);
 }
 
 }  // namespace
 
 void Init(scoped_ptr<CommandExecutor> executor) {
   g_command_executor = executor.release();
   // We do not call CommandExecutor::Init here because you can't do some things
   // (e.g., creating threads) during DLL loading on Windows.
 }
 
@@ skipping 63 matching lines @@
   // 3. Add Chrome command-line switch for socket/pipe that Chrome listens
   //    to and exits if the pipe is closed. This is how the old
   //    TestingAutomationProvider worked. However, this doesn't clean up
   //    temp directories, unless we make Chrome clean its own directory too.
   //    If Chrome crashes the directory would be leaked.
   base::DictionaryValue params;
   StatusCode status_code;
   scoped_ptr<base::Value> value;
   std::string session_id;
   g_command_executor->ExecuteCommand(
-      "quitAll", params, "", &status_code, &value, &session_id);
+      "quitAll", params, std::string(), &status_code, &value, &session_id);
   delete g_command_executor;
 }