patch 8.2.3871: list.c contains code for dict and blob

Problem:    List.c contains code for dict and blob.
Solution:   Refactor to put code where it belongs. (Yegappan Lakshmanan,
            closes #9386)
diff --git a/src/proto/strings.pro b/src/proto/strings.pro
index 4dba9b1..778ec90 100644
--- a/src/proto/strings.pro
+++ b/src/proto/strings.pro
@@ -21,6 +21,9 @@
 int has_non_ascii(char_u *s);
 char_u *concat_str(char_u *str1, char_u *str2);
 char_u *string_quote(char_u *str, int function);
+long string_count(char_u *haystack, char_u *needle, int ic);
+void string_filter_map(char_u *str, filtermap_T filtermap, typval_T *expr, typval_T *rettv);
+void string_reduce(typval_T *argvars, char_u *func_name, funcexe_T *funcexe, typval_T *rettv);
 void f_byteidx(typval_T *argvars, typval_T *rettv);
 void f_byteidxcomp(typval_T *argvars, typval_T *rettv);
 void f_charidx(typval_T *argvars, typval_T *rettv);