[build] Requires xulrunner 1.9.1.x on openSUSE, required by gjs

gjs needs xulrunner 1.9.1 (see bug 627383), install the right package
on openSUSE distributions.

https://bugzilla.gnome.org/show_bug.cgi?id=627384

tools/build/gnome-shell-build-setup.sh

@@ -128,7 +128,7 @@ if test "x$system" = xSUSE -o "x$system" = "xSUSE LINUX" ; then
     curl \
     bison flex gtk-doc gnome-common gnome-doc-utils-devel \
     libtiff-devel cups-devel libffi-devel gnome-desktop-devel libwnck-devel \
-    xorg-x11-proto-devel readline-devel mozilla-xulrunner190-devel \
+    xorg-x11-proto-devel readline-devel mozilla-xulrunner191-devel \
     libcroco-devel xorg-x11-devel xorg-x11 xorg-x11-server-extra \
     ; do
       if ! rpm -q $pkg > /dev/null 2>&1; then