patch 8.2.0368: Vim9: import that redefines local variable does not fail
Problem: Vim9: import that redefines local variable does not fail.
Solution: Check for already defined symbols.
diff --git a/src/proto/vim9compile.pro b/src/proto/vim9compile.pro
index 61a6281..6905fc2 100644
--- a/src/proto/vim9compile.pro
+++ b/src/proto/vim9compile.pro
@@ -1,4 +1,5 @@
/* vim9compile.c */
+int check_defined(char_u *p, int len, cctx_T *cctx);
char_u *skip_type(char_u *start);
type_T *parse_type(char_u **arg, garray_T *type_list);
char *vartype_name(vartype_T type);