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

chrome/browser/search/local_ntp_source.cc

 // Copyright 2013 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/search/local_ntp_source.h"
 
 #include "base/logging.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/string_util.h"
 #include "chrome/common/url_constants.h"
@@ skipping 56 matching lines @@
   if (path == kHtmlFilename)
     return "text/html";
   if (path == kJSFilename)
     return "application/javascript";
   if (path == kCssFilename)
     return "text/css";
   if (path == kCloseBarFilename || path == kCloseBarHoverFilename ||
       path == kCloseBarActiveFilename) {
     return "image/png";
   }
-  return "";
+  return std::string();
 }
 
 bool LocalNtpSource::ShouldServiceRequest(
     const net::URLRequest* request) const {
   DCHECK(request->url().host() == chrome::kChromeSearchLocalNtpHost);
 
   if (request->url().SchemeIs(chrome::kChromeSearchScheme)) {
     DCHECK(StartsWithASCII(request->url().path(), "/", true));
     std::string filename = request->url().path().substr(1);
     return filename == kHtmlFilename || filename == kJSFilename ||
            filename == kCssFilename || filename == kCloseBarFilename ||
            filename == kCloseBarHoverFilename ||
            filename == kCloseBarActiveFilename;
   }
   return false;
 }