[poppler] [PATCH] Arthur backend fixes; poppler-qt4 direct rendering

[Matthias Fauconneau]

> As you can see Pino commited your patch and it will be part of poppler
> 0.15.2
> that i plan to release "soon (TM)"

Thanks for the commit.
Since I recently switched to nouveau, GL rendering broke :(
While raster painter works fine, it doesn't really provide an
interactive framerate :)
I'll have to see if I can make nouveau better support Qt GL painter.