Enforce the 'requirements' field in manifests.

chrome/browser/extensions/extension_service.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_EXTENSION_SERVICE_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_SERVICE_H_
 
 #include <list>
 #include <map>
 #include <set>
@@ skipping 385 matching lines @@
 
   // Adds |extension| to this ExtensionService and notifies observers than an
   // extension has been loaded.  Called by the backend after an extension has
   // been loaded from a file and installed.
   virtual void AddExtension(const extensions::Extension* extension) OVERRIDE;
 
   // Called by the backend when an extension has been installed.
   void OnExtensionInstalled(
       const extensions::Extension* extension,
       bool from_webstore,
-      const StringOrdinal& page_ordinal);
+      const StringOrdinal& page_ordinal,
+      const std::vector<std::string>& requirement_errors);
 
   // Initializes the |extension|'s active permission set and disables the
   // extension if the privilege level has increased (e.g., due to an upgrade).
   void InitializePermissions(const extensions::Extension* extension);
 
   // Go through each extensions in pref, unload blacklisted extensions
   // and update the blacklist state in pref.
   virtual void UpdateExtensionBlacklist(
       const std::vector<std::string>& blacklist) OVERRIDE;
 
@@ skipping 445 matching lines @@
   scoped_ptr<ExtensionErrorUI> extension_error_ui_;
 
   FRIEND_TEST_ALL_PREFIXES(ExtensionServiceTest,
                            InstallAppsWithUnlimtedStorage);
   FRIEND_TEST_ALL_PREFIXES(ExtensionServiceTest,
                            InstallAppsAndCheckStorageProtection);
   DISALLOW_COPY_AND_ASSIGN(ExtensionService);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_SERVICE_H_