[cairo] Problem with directly drawing to a GDI context

[Andrej Mitrovic]

Thanks for the info. I'm really only going to use cairo for drawing (I
won't need to flush/mark dirty) and I'm ok with using a backbuffer. I
actually thought that drawing directly to a DC would be faster, hence
I was trying to avoid a backbuffer.

This example recreates the context on every paint but I'm not using
this type of code, this was just for demonstration. :)