If the panel finish is damaged beyond this simple fix, then I go to a black dye, like Griot's Garage Bumper & Trim Reconditioner. Beyond that, a repaint would be called for. Repainting is a problem with the blue panels, as a color match would be unlikely.
Finally, the rubber edge gasket is adhered with a rubber cement product called, fittingly, Goop.
Job done!