Replace ToLower calls to the new format

components/history/core/browser/url_utils.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 "components/history/core/browser/url_utils.h"
 
 #include <algorithm>
 
 #include "base/strings/string_util.h"
 #include "url/gurl.h"
@@ skipping 70 matching lines @@
     return GURL::EmptyGURL();
   url::Component comp;
   comp.len = static_cast<int>(new_scheme.length());
   GURL::Replacements replacement;
   replacement.SetScheme(new_scheme.c_str(), comp);
   return url.ReplaceComponents(replacement);
 }
 
 std::string HostForTopHosts(const GURL& url) {
   std::string host = url.host();
-  base::StringToLowerASCII(&host);
   if (base::StartsWith(host, "www.", base::CompareCase::SENSITIVE))
     host.assign(host, 4, std::string::npos);
   return host;
 }
 
 }  // namespace history