GParam: make G_PARAM_USER_MASK unsigned
GParam: make G_PARAM_USER_MASK unsigned

UBSan considers left-shifting a negative number to be undefined
behaviour (per
<http://www.open-std.org/jtc1/sc22/wg14/www/docs/dr_081.html> it is
implementation-defined in C89, but according to
<https://llvm.org/bugs/show_bug.cgi?id=17490> it is undefined in C99).

Signed-off-by: Simon McVittie <0e1aea601907c1a85c2dc96e5ea37e23c58d2e9b@debian.org>
Bug: https://bugzilla.gnome.org/show_bug.cgi?id=775510
Reviewed-by: Colin Walters

johne53/MB3Glib,endlessm/glib,endlessm/glib,johne53/MB3Glib,endlessm/glib,johne53/MB3Glib,endlessm/glib,johne53/MB3Glib,johne53/MB3Glib,johne53/MB3Glib,endlessm/glib