refactor: ginify Tray (#22822)

* refactor: ginify Tray

* lint

* improve argument parsing logic

* remove redundant imports from tray.js

* new Tray produces an instanceof Tray

* make Constructible generic

* lint

* clean up on exit

shell/browser/api/ui_event.h

@@ -0,0 +1,22 @@
+// Copyright (c) 2020 Slack Technologies, Inc.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+#ifndef SHELL_BROWSER_API_UI_EVENT_H_
+#define SHELL_BROWSER_API_UI_EVENT_H_
+
+namespace v8 {
+class Object;
+template <typename T>
+class Local;
+}  // namespace v8
+
+namespace electron {
+namespace api {
+
+v8::Local<v8::Object> CreateEventFromFlags(int flags);
+
+}  // namespace api
+}  // namespace electron
+
+#endif  // SHELL_BROWSER_API_UI_EVENT_H_