fix(xgamma): avoid unexpected expansion by -W

Author: akinomyoga

completions/xgamma

@@ -33,7 +33,7 @@ _comp_cmd_xgamma()
                 local t screens=$(xrandr --query 2>/dev/null | command sed -ne \
                     '/^Screen /s|^Screen \{1,\}\(.*\):.*$|\1|p' 2>/dev/null)
                 t="${cur#:}"
-                COMPREPLY=($(compgen -P "${t%.*}." -W "$screens" -- \
+                COMPREPLY=($(compgen -P "${t%.*}." -W '$screens' -- \
                     "${cur##*.}"))
             elif [[ $cur != *:* ]]; then
                 # complete hostnames