Fix also the other place where maskstride was calculated.
Fix also the other place where maskstride was calculated.

davidt/gtk,jadahl/gtk,Distrotech/gtk,zsx/gtk,ebassi/gtk,chipx86/gtk,chergert/gtk,Sidnioulz/SandboxGtk,ebassi/gtk,simokivimaki/gtk,grubersjoe/adwaita,davidgumberg/gtk,ebassi/gtk,zsx/gtk,ahodesuka/gtk,jigpu/gtk,Lyude/gtk-,davidgumberg/gtk,Adamovskiy/gtk,ahodesuka/gtk,Distrotech/gtk2,simokivimaki/gtk,ahodesuka/gtk,Unity-Technologies/gtk,davidgumberg/gtk,johne53/MB3Gtk-2,jessevdk/gtk,bratsche/gtk-,chipx86/gtk,davidt/gtk,chergert/gtk,Adamovskiy/gtk,Sidnioulz/SandboxGtk,zsx/gtk,zsx/gtk,Lyude/gtk-,Lyude/gtk-,jadahl/gtk,davidt/gtk,msteinert/gtk,bratsche/gtk-,ebassi/gtk,bratsche/gtk-,Lyude/gtk-,davidgumberg/gtk,Sidnioulz/SandboxGtk,Lyude/gtk-,grubersjoe/adwaita,jadahl/gtk,Adamovskiy/gtk,johne53/MB3Gtk-2,alexlarsson/gtk,Distrotech/gtk,msteinert/gtk,chipx86/gtk,ebassi/gtk,chergert/gtk,msteinert/gtk,Unity-Technologies/gtk,jadahl/gtk,bratsche/gtk-,alexlarsson/gtk,Lyude/gtk-,davidt/gtk,davidgumberg/gtk,Unity-Technologies/gtk,grubersjoe/adwaita,johne53/MB3Gtk-2,zsx/gtk,jessevdk/gtk,davidgumberg/gtk,Adamovskiy/gtk,jessevdk/gtk,alexlarsson/gtk,Distrotech/gtk2,grubersjoe/adwaita,alexlarsson/gtk,jessevdk/gtk,grubersjoe/adwaita,simokivimaki/gtk,jadahl/gtk,Distrotech/gtk2,jadahl/gtk,Sidnioulz/SandboxGtk,jigpu/gtk,jessevdk/gtk,msteinert/gtk,alexlarsson/gtk,Adamovskiy/gtk,alexlarsson/gtk,johne53/MB3Gtk-2,bratsche/gtk-,nacho/gtk-,Distrotech/gtk,bratsche/gtk-,nacho/gtk-,alexlarsson/gtk,chipx86/gtk,msteinert/gtk,Distrotech/gtk2,jessevdk/gtk,johne53/MB3Gtk-2,jigpu/gtk,Adamovskiy/gtk,ahodesuka/gtk,ahodesuka/gtk,nacho/gtk-,chergert/gtk,grubersjoe/adwaita,Distrotech/gtk2,jigpu/gtk,Sidnioulz/SandboxGtk,simokivimaki/gtk,Distrotech/gtk,ebassi/gtk,nacho/gtk-,grubersjoe/adwaita,Unity-Technologies/gtk,simokivimaki/gtk,jadahl/gtk,Lyude/gtk-,Lyude/gtk-,alexlarsson/gtk,Distrotech/gtk2,jigpu/gtk,chergert/gtk,jigpu/gtk,chergert/gtk,nacho/gtk-,davidt/gtk,Adamovskiy/gtk,grubersjoe/adwaita,Adamovskiy/gtk,jigpu/gtk,ahodesuka/gtk,ahodesuka/gtk,davidt/gtk,jigpu/gtk,Sidnioulz/SandboxGtk,davidgumberg/gtk,chipx86/gtk,chergert/gtk,Distrotech/gtk,davidgumberg/gtk,chergert/gtk,Unity-Technologies/gtk,msteinert/gtk,ahodesuka/gtk,simokivimaki/gtk,jessevdk/gtk,jadahl/gtk