Disallow packing or loading unpacked manifest v1 extensions.

chrome/browser/extensions/pack_extension_job.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_PACK_EXTENSION_JOB_H_
 #define CHROME_BROWSER_EXTENSIONS_PACK_EXTENSION_JOB_H_
 
 #include <string>
 
 #include "base/file_path.h"
@@ skipping 49 matching lines @@
   void ReportFailureOnClientThread(const std::string& error,
                                    ExtensionCreator::ErrorType error_type);
 
   content::BrowserThread::ID client_thread_id_;
   Client* client_;
   FilePath root_directory_;
   FilePath key_file_;
   FilePath crx_file_out_;
   FilePath key_file_out_;
   bool asynchronous_;
-  int run_flags_;  // Bitset of ExtensionCreator::RunFlags values
+  int run_flags_;  // Bitset of ExtensionCreator::RunFlags values - we always
+                   // assume kRequireModernManifestVersion, though.
 
   DISALLOW_COPY_AND_ASSIGN(PackExtensionJob);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_PACK_EXTENSION_JOB_H_