Restore get_window function
Restore get_window function

nicokoch/glium,carbidegames/glium,christopheraugustus/glium,rozaliev/glium,acolley/glium,tomaka/glium,TyOverby/glium,caldwell/glium,glium/glium,bvssvni/glium,cpjreynolds/glium,sdotz/glium,binsoftware/glium