bug 156593, Remove the dependence to gtk1 when the default toolkit is gtk2. This checkin fix a error in last patch

configure.in

@@ -4269,7 +4269,7 @@ MOZ_ARG_WITHOUT_BOOL(libIDL,
 
 if test "$SKIP_IDL_CHECK" = "no"
 then
-    if test $MOZ_ENABLE_GTK2 = 1; then
+    if test "$MOZ_ENABLE_GTK2"; then
         AM_PATH_LIBIDL_2($LIBIDL_VERSION,,_LIBIDL_NOT_FOUND=1)
     else
         AM_PATH_LIBIDL($LIBIDL_VERSION,,_LIBIDL_NOT_FOUND=1)