Do not test the event mask of implicit grabs
Do not test the event mask of implicit grabs

The quartz backend simulates the semantics of XGrabPointer, as a part of
this it checks the event mask of the grab.  However, implicit grabs on X
do not go through XGrabPointer and thus the quartz backend should not check
the event mask for these.  This fixes various "the UI got stuck" cases.

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