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

chrome/browser/profiles/profile_downloader_unittest.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/browser/profiles/profile_downloader.h"
 
 #include "base/utf_string_conversions.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
@@ skipping 50 matching lines @@
       true);
 
   // URL with unknown format.
   VerifyWithNameAndURL(
       "Pat Smith",
       "http://lh0.ggpht.com/-abcd1aBCDEf/AAAA/AAA_A/",
       "http://lh0.ggpht.com/-abcd1aBCDEf/AAAA/AAA_A/",
       true);
 
   // Data with only name.
-  VerifyWithNameAndURL("Pat Smith", "", "", true);
+  VerifyWithNameAndURL("Pat Smith", std::string(), std::string(), true);
 
   // Data with only URL.
   VerifyWithNameAndURL(
-      "",
+      std::string(),
       "https://example.com/--Abc/AAAAAAAAAAI/AAAAAAAAACQ/Efg/photo.jpg",
       "https://example.com/--Abc/AAAAAAAAAAI/AAAAAAAAACQ/Efg/s32-c/photo.jpg",
       true);
 
   // Data without name or URL.
-  VerifyWithNameAndURL("", "", "", false);
+  VerifyWithNameAndURL(std::string(), std::string(), std::string(), false);
 
   // Data with an invalid URL.
-  VerifyWithNameAndURL( "", "invalid url", "", false);
+  VerifyWithNameAndURL(std::string(), "invalid url", std::string(), false);
 }
 
 TEST_F(ProfileDownloaderTest, DefaultURL) {
   // Empty URL should be default photo
-  EXPECT_TRUE(ProfileDownloader::IsDefaultProfileImageURL(""));
+  EXPECT_TRUE(ProfileDownloader::IsDefaultProfileImageURL(std::string()));
   // Picasa default photo
   EXPECT_TRUE(ProfileDownloader::IsDefaultProfileImageURL(
       "https://example.com/-4/AAAAAAAAAAA/AAAAAAAAAAE/G/s64-c/photo.jpg"));
   // Not default G+ photo
   EXPECT_FALSE(ProfileDownloader::IsDefaultProfileImageURL(
       "https://example.com/-4/AAAAAAAAAAI/AAAAAAAAAAA/G/photo.jpg"));
   // Not default with 6 components
   EXPECT_FALSE(ProfileDownloader::IsDefaultProfileImageURL(
       "https://example.com/-4/AAAAAAAAAAI/AAAAAAAAACQ/Efg/photo.jpg"));
   // Not default with 7 components
   EXPECT_FALSE(ProfileDownloader::IsDefaultProfileImageURL(
       "https://example.com/-4/AAAAAAAAAAI/AAAAAAAAACQ/Efg/s32-c/photo.jpg"));
 }