Add Window.setFocus to API

[Disorrder]

I want to realize window "blink" effect making focus on and off. I've tried to realize by setting active to window and then to desktop, but active sets only if window is minimized. I have to use node-ffi for this
https://msdn.microsoft.com/en-us/library/windows/desktop/ms646312(v=vs.85).aspx