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

chrome/common/content_settings_pattern_parser.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/common/content_settings_pattern_parser.h"
 
 #include "base/string_util.h"
 #include "chrome/common/url_constants.h"
 #include "extensions/common/constants.h"
 #include "googleurl/src/gurl.h"
@@ skipping 180 matching lines @@
 std::string PatternParser::ToString(
     const ContentSettingsPattern::PatternParts& parts) {
   // Return the most compact form to support legacy code and legacy pattern
   // strings.
   if (parts.is_scheme_wildcard &&
       parts.has_domain_wildcard &&
       parts.host.empty() &&
       parts.is_port_wildcard)
     return "*";
 
-  std::string str = "";
+  std::string str;
   if (!parts.is_scheme_wildcard)
     str += parts.scheme + content::kStandardSchemeSeparator;
 
   if (parts.scheme == chrome::kFileScheme) {
     if (parts.is_path_wildcard)
       return str + kUrlPathSeparator + kPathWildcard;
     else
       return str + parts.path;
   }
 
@@ skipping 11 matching lines @@
   }
 
   if (!parts.is_port_wildcard) {
     str += std::string(kUrlPortSeparator) + parts.port;
   }
 
   return str;
 }
 
 }  // namespace content_settings