Enable the "options_ui" manifest key on stable channel.

extensions/common/api/_manifest_features.json

 // Copyright 2014 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.
 
 // This features file defines manifest keys implemented under src/extensions.
 // See extensions/common/features/* to understand this file, in particular
 // feature.h, simple_feature.h, and base_feature_provider.h.
 
 // To add a new whitelisted ID, SHA-1 it and force it to uppercase. In Bash:
 //
@@ skipping 153 matching lines @@
     "channel": "stable",
     "extension_types": "all"
   },
   "offline_enabled": {
     "channel": "stable",
     "extension_types": [
       "extension", "legacy_packaged_app", "hosted_app", "platform_app"
     ]
   },
   "options_ui": {
-    "channel": "trunk",
+    "channel": "stable",
     "extension_types": ["extension", "legacy_packaged_app"]
   },
   "sandbox": {
     "channel": "stable",
     "extension_types": [
       "extension", "platform_app", "legacy_packaged_app"
     ],
     "min_manifest_version": 2
   },
   "sockets": {
@@ skipping 16 matching lines @@
       "extension_types": ["platform_app"],
       "location": "component"
     }
   ],
   "webview": {
     "channel": "stable",
     "extension_types": ["platform_app"],
     "min_manifest_version": 2
   }
 }