[Extensions Page MD] Stub out a materialized extensions page

chrome/browser/resources/md_extensions/compiled_resources.gyp

 # 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.
 {
   'targets': [
     {
-      'target_name': 'certificate_manager_dialog',
-       'variables': {
+      'target_name': 'manager',
+      'variables': {
         'depends': [
-          '../../../../chrome/browser/resources/options/compiled_resources.gyp:options_bundle',
+          '../../../../ui/webui/resources/js/cr.js',
         ],
-        'externs': ['<(EXTERNS_DIR)/chrome_send.js'],
+        'externs': [
+          '<(EXTERNS_DIR)/chrome_send.js',
+        ],
       },
       'includes': ['../../../../third_party/closure_compiler/compile_js.gypi'],
     }
   ],
 }