Revert "Move ExtensionCache to //extensions"

chrome/browser/extensions/updater/extension_updater.h

 // 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_UPDATER_H_
 #define CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_UPDATER_H_
 
 #include <list>
 #include <map>
 #include <set>
@@ skipping 107 matching lines @@
   // hasn't been performed yet.  This is used mostly by tests; calling
   // code should just call CheckSoon().
   bool WillCheckSoon() const;
 
   // Changes the params that are used for the automatic periodic update checks,
   // as well as for explicit calls to CheckSoon.
   void set_default_check_params(const CheckParams& params) {
     default_params_ = params;
   }
 
-  // Overrides the extension cache with |extension_cache| for testing.
-  void SetExtensionCacheForTesting(ExtensionCache* extension_cache);
-
  private:
   friend class ExtensionUpdaterTest;
   friend class ExtensionUpdaterFileHandler;
 
   // FetchedCRXFile holds information about a CRX file we fetched to disk,
   // but have not yet installed.
   struct FetchedCRXFile {
     FetchedCRXFile();
     FetchedCRXFile(const std::string& id,
                    const base::FilePath& path,
@@ skipping 151 matching lines @@
   std::set<std::string> forced_updates_;
 
   base::WeakPtrFactory<ExtensionUpdater> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionUpdater);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_UPDATER_H_