DevTools: request app banner from DevTools without #enable-add-to-shelf flag while emulating.

third_party/WebKit/Source/devtools/front_end/components/RequestAppBannerActionDelegate.js

+// Copyright 2016 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.
+
+/**
+ * @constructor
+ * @implements {WebInspector.ActionDelegate}
+ */
+WebInspector.RequestAppBannerActionDelegate = function()
+{
+}
+
+WebInspector.RequestAppBannerActionDelegate.prototype = {
+    /**
+     * @override
+     * @param {!WebInspector.Context} context
+     * @param {string} actionId
+     * @return {boolean}
+     */
+    handleAction: function(context, actionId)
+    {
+        var target = WebInspector.targetManager.mainTarget();
+        if (target && target.isPage()) {
+            target.pageAgent().requestAppBanner();
+            WebInspector.console.show();
+        }
+        return true;
+    }
+}