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

chrome/browser/google_apis/test_server/http_server_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 "chrome/browser/google_apis/test_server/http_server.h"
 
 #include "base/stringprintf.h"
 #include "base/threading/thread.h"
 #include "chrome/browser/google_apis/test_server/http_request.h"
 #include "chrome/browser/google_apis/test_server/http_response.h"
@@ skipping 20 matching lines @@
 }
 
 // Gets the content type from the given URLFetcher.
 std::string GetContentTypeFromFetcher(const net::URLFetcher& fetcher) {
   const net::HttpResponseHeaders* headers = fetcher.GetResponseHeaders();
   if (headers) {
     std::string content_type;
     if (headers->GetMimeType(&content_type))
       return content_type;
   }
-  return "";
+  return std::string();
 }
 
 }  // namespace
 
 class HttpServerTest : public testing::Test,
                        public net::URLFetcherDelegate {
  public:
   HttpServerTest()
       : num_responses_received_(0),
         num_responses_expected_(0),
@@ skipping 165 matching lines @@
   EXPECT_EQ("text/html", GetContentTypeFromFetcher(*fetcher2));
 
   EXPECT_EQ(net::URLRequestStatus::SUCCESS, fetcher3->GetStatus().status());
   EXPECT_EQ(NOT_FOUND, fetcher3->GetResponseCode());
   EXPECT_EQ("No chocolates", GetContentFromFetcher(*fetcher3));
   EXPECT_EQ("text/plain", GetContentTypeFromFetcher(*fetcher3));
 }
 
 }  // namespace test_server
 }  // namespace google_apis