patch 9.0.1231: completion of :runtime does not handle {where} argument

Problem:    Completion of :runtime does not handle {where} argument.
Solution:   Parse the {where} argument. (closes #11863)
diff --git a/src/proto/cmdexpand.pro b/src/proto/cmdexpand.pro
index 2fb543a..1e2b148 100644
--- a/src/proto/cmdexpand.pro
+++ b/src/proto/cmdexpand.pro
@@ -14,7 +14,7 @@
 void set_expand_context(expand_T *xp);
 void set_cmd_context(expand_T *xp, char_u *str, int len, int col, int use_ccline);
 int expand_cmdline(expand_T *xp, char_u *str, int col, int *matchcount, char_u ***matches);
-void globpath(char_u *path, char_u *file, garray_T *ga, int expand_options);
+void globpath(char_u *path, char_u *file, garray_T *ga, int expand_options, int dirs);
 int wildmenu_translate_key(cmdline_info_T *cclp, int key, expand_T *xp, int did_wild_list);
 int wildmenu_process_key(cmdline_info_T *cclp, int key, expand_T *xp);
 void wildmenu_cleanup(cmdline_info_T *cclp);