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

chrome/test/chromedriver/chrome/navigation_tracker_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 <string>
 
 #include "base/compiler_specific.h"
 #include "base/json/json_reader.h"
 #include "base/values.h"
 #include "chrome/test/chromedriver/chrome/navigation_tracker.h"
@@ skipping 155 matching lines @@
  private:
   bool is_loading_;
   std::string send_event_first_;
   base::DictionaryValue* send_event_first_params_;
 };
 
 }  // namespace
 
 TEST(NavigationTracker, UnknownStateForcesStart) {
   base::DictionaryValue params;
-  DeterminingLoadStateDevToolsClient client(true, "", &params);
+  DeterminingLoadStateDevToolsClient client(true, std::string(), &params);
   NavigationTracker tracker(&client);
   ASSERT_NO_FATAL_FAILURE(AssertPendingState(&tracker, "f", true));
 }
 
 TEST(NavigationTracker, UnknownStateForcesStartReceivesStop) {
   base::DictionaryValue params;
   DeterminingLoadStateDevToolsClient client(
       true, "Page.frameStoppedLoading", &params);
   NavigationTracker tracker(&client);
   ASSERT_NO_FATAL_FAILURE(AssertPendingState(&tracker, "f", false));
 }