Enable visibleOnAllWorkspaces on 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 35 matching lines @@
     "contexts": ["blessed_extension"],
     "extension_types": ["extension"],
     "noparent": true,
     "component_extensions_auto_granted": false,
     "whitelist": [
       "B9EF10DDFEA11EF77873CC5009809E5037FC4C7A",  // Google input tools
       "06BE211D5F014BAB34BC22D9DDA09C63A81D828E",  // Official xkb extension
       "F94EE6AB36D6C6588670B2B01EB65212D9C64E33"   // Open source xkb extension
     ]
   }],
-  // This does not need to be a complex feature if we could set "noparent" here.
-  // But set "noparent" makes this feature available on stable channel. The
-  // issue is tracked in crbug.com/415750.
-  "app.window.canSetVisibleOnAllWorkspaces": [{
-    "contexts": ["blessed_extension"],
-    "channel": "dev"
-  }],
   "app.currentWindowInternal": {
     "noparent": true,
     "internal": true,
     "channel": "stable",
     "contexts": ["blessed_extension"]
   },
   "app.currentWindowInternal.setShape": {
     "dependencies": ["permission:app.window.shape"],
     "contexts": ["blessed_extension"]
   },
@@ skipping 350 matching lines @@
   }],
   "webViewRequest": [{
     "dependencies": ["permission:webview"],
     "contexts": ["blessed_extension"]
   }, {
     "channel": "stable",
     "contexts": ["webui"],
     "matches": ["chrome://chrome-signin/*", "chrome://oobe/*"]
   }]
 }