GlobalShortcut_win: check for gkey != NULL in gkey handling.
GlobalShortcut_win: check for gkey != NULL in gkey handling.

With the ability to enable/disable GKey support at runtime, we
need these extra checks to avoid crashes.

Lartza/mumble,Lartza/mumble,Lartza/mumble,Lartza/mumble,Lartza/mumble,Lartza/mumble,Lartza/mumble,Lartza/mumble