Allow extension APIs to be restricted to a subset of Chrome channels using the

chrome/common/extensions/api/bookmarks.json

 // 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.
 
 [
   {
     "namespace": "bookmarks",
     "uses_feature_system": true,
+    "supported_channel": "stable",
     "dependencies": ["permission:bookmarks"],
     "contexts": ["blessed_extension"],
     "types": [
       {
         "id": "BookmarkTreeNode",
         "type": "object",
         "description": "A node (either a bookmark or a folder) in the bookmark tree.  Child nodes are ordered within their parent folder.",
         "properties": {
           "id": {"type": "string", "minimum": 0, "description": "The unique identifier for the node. IDs are unique within the current profile, and they remain valid even after the browser is restarted."},
           "parentId": {"type": "string", "minimum": 0, "optional": true, "description": "The <code>id</code> of the parent folder.  Omitted for the root node."},
@@ skipping 311 matching lines @@
       },
       {
         "name": "onImportEnded",
         "type": "function",
         "description": "Fired when a bookmark import session is ended.",
         "parameters": []
       }
     ]
   }
 ]