Move Singleton and related structs to namespace base

components/url_formatter/url_formatter.cc

 // Copyright 2015 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/url_formatter/url_formatter.h"
 
 #include <algorithm>
 #include <map>
 #include <utility>
 
@@ skipping 289 matching lines @@
   // Cyrillic letters), but it can be more dangerous.
   return !lang.substr(0, 2).compare("zh") || !lang.substr(0, 2).compare("ja") ||
          !lang.substr(0, 2).compare("ko");
 }
 
 typedef std::map<std::string, icu::UnicodeSet*> LangToExemplarSetMap;
 
 class LangToExemplarSet {
  public:
   static LangToExemplarSet* GetInstance() {
-    return Singleton<LangToExemplarSet>::get();
+    return base::Singleton<LangToExemplarSet>::get();
   }
 
  private:
   LangToExemplarSetMap map;
   LangToExemplarSet() {}
   ~LangToExemplarSet() {
     STLDeleteContainerPairSecondPointers(map.begin(), map.end());
   }
 
-  friend class Singleton<LangToExemplarSet>;
-  friend struct DefaultSingletonTraits<LangToExemplarSet>;
+  friend class base::Singleton<LangToExemplarSet>;
+  friend struct base::DefaultSingletonTraits<LangToExemplarSet>;
   friend bool GetExemplarSetForLang(const std::string&, icu::UnicodeSet**);
   friend void SetExemplarSetForLang(const std::string&, icu::UnicodeSet*);
 
   DISALLOW_COPY_AND_ASSIGN(LangToExemplarSet);
 };
 
 bool GetExemplarSetForLang(const std::string& lang,
                            icu::UnicodeSet** lang_set) {
   const LangToExemplarSetMap& map = LangToExemplarSet::GetInstance()->map;
   LangToExemplarSetMap::const_iterator pos = map.find(lang);
@@ skipping 466 matching lines @@
       url.possibly_invalid_spec(), url.parsed_for_possibly_invalid_spec().host,
       HostComponentTransform(languages), output, NULL, NULL);
 }
 
 base::string16 IDNToUnicode(const std::string& host,
                             const std::string& languages) {
   return IDNToUnicodeWithAdjustments(host, languages, NULL);
 }
 
 }  // url_formatter