Promote hid.onDeviceAdded and hid.onDeviceRemoved to stable.

extensions/common/api/_api_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 extension APIs implemented under src/extensions.
 // See extensions/common/features/* to understand this file, in particular
 // feature.h, simple_feature.h, and base_feature_provider.h.
 //
 // Note that specifying "web_page", "blessed_web_page", or "all" as a context
 // type will require manually updating chrome/renderer/resources/dispatcher.cc.
@@ skipping 144 matching lines @@
       "internal": true,
       "channel": "trunk",
       "contexts": "all",
       "matches": ["<all_urls>"]
     }
   ],
   "hid": {
     "dependencies": ["permission:hid"],
     "contexts": ["blessed_extension"]
   },
-  "hid.onDeviceAdded": {
-    "channel": "dev",
-    "dependencies": ["permission:hid"],
-    "contexts": ["blessed_extension"]
-  },
-  "hid.onDeviceRemoved": {
-    "channel": "dev",
-    "dependencies": ["permission:hid"],
-    "contexts": ["blessed_extension"]
-  },
   "management": {
     "dependencies": ["permission:management"],
     "contexts": ["blessed_extension"]
   },
   "management.getPermissionWarningsByManifest": {
     "dependencies": [],
     "channel": "stable",
     "extension_types": ["extension", "legacy_packaged_app", "platform_app"]
   },
   "management.getSelf": {
@@ skipping 204 matching lines @@
   }],
   "webViewRequest": [{
     "dependencies": ["permission:webview"],
     "contexts": ["blessed_extension"]
   }, {
     "channel": "stable",
     "contexts": ["webui"],
     "matches": ["chrome://chrome-signin/*", "chrome://oobe/*"]
   }]
 }