Removing global function agg_item_charsets_for_string_result().

Moving agg_arg_charsets_for_string_result() and
agg_arg_charsets_for_string_result_with_comparison() inside
"protected" section in Item_func_or_sum.

sql/item.h

@@ -2162,16 +2162,6 @@ bool agg_item_set_converter(DTCollation &coll, const char *fname,
 bool agg_item_charsets(DTCollation &c, const char *name,
                        Item **items, uint nitems, uint flags, int item_sep);
 inline bool
-agg_item_charsets_for_string_result(DTCollation &c, const char *name,
-                                    Item **items, uint nitems,
-                                    int item_sep= 1)
-{
-  uint flags= MY_COLL_ALLOW_SUPERSET_CONV |
-              MY_COLL_ALLOW_COERCIBLE_CONV |
-              MY_COLL_ALLOW_NUMERIC_CONV;
-  return agg_item_charsets(c, name, items, nitems, flags, item_sep);
-}
-inline bool
 agg_item_charsets_for_comparison(DTCollation &c, const char *name,
                                  Item **items, uint nitems,
                                  int item_sep= 1)
@@ -3626,6 +3616,39 @@ public:
 */
 class Item_func_or_sum: public Item_result_field, public Item_args
 {
+protected:
+  /*
+    Aggregate arguments for string result, e.g: CONCAT(a,b)
+    - convert to @@character_set_connection if all arguments are numbers
+    - allow DERIVATION_NONE
+  */
+  bool agg_arg_charsets_for_string_result(DTCollation &c,
+                                          Item **items, uint nitems,
+                                          int item_sep= 1)
+  {
+    uint flags= MY_COLL_ALLOW_SUPERSET_CONV |
+                MY_COLL_ALLOW_COERCIBLE_CONV |
+                MY_COLL_ALLOW_NUMERIC_CONV;
+    return agg_item_charsets(c, func_name(), items, nitems, flags, item_sep);
+  }
+  /*
+    Aggregate arguments for string result, when some comparison
+    is involved internally, e.g: REPLACE(a,b,c)
+    - convert to @@character_set_connection if all arguments are numbers
+    - disallow DERIVATION_NONE
+  */
+  bool agg_arg_charsets_for_string_result_with_comparison(DTCollation &c,
+                                                          Item **items,
+                                                          uint nitems,
+                                                          int item_sep= 1)
+  {
+    uint flags= MY_COLL_ALLOW_SUPERSET_CONV |
+                MY_COLL_ALLOW_COERCIBLE_CONV |
+                MY_COLL_ALLOW_NUMERIC_CONV |
+                MY_COLL_DISALLOW_NONE;
+    return agg_item_charsets(c, func_name(), items, nitems, flags, item_sep);
+  }
+
 public:
   Item_func_or_sum(THD *thd): Item_result_field(thd), Item_args() {}
   Item_func_or_sum(THD *thd, Item *a): Item_result_field(thd), Item_args(a) { }

sql/item_func.h

@@ -192,18 +192,6 @@ public:
   {
     return agg_item_charsets(c, func_name(), items, nitems, flags, item_sep);
   }
-  /*
-    Aggregate arguments for string result, e.g: CONCAT(a,b)
-    - convert to @@character_set_connection if all arguments are numbers
-    - allow DERIVATION_NONE
-  */
-  bool agg_arg_charsets_for_string_result(DTCollation &c,
-                                          Item **items, uint nitems,
-                                          int item_sep= 1)
-  {
-    return agg_item_charsets_for_string_result(c, func_name(),
-                                               items, nitems, item_sep);
-  }
   /*
     Aggregate arguments for comparison, e.g: a=b, a LIKE b, a RLIKE b
     - don't convert to @@character_set_connection if all arguments are numbers
@@ -216,21 +204,6 @@ public:
     return agg_item_charsets_for_comparison(c, func_name(),
                                             items, nitems, item_sep);
   }
-  /*
-    Aggregate arguments for string result, when some comparison
-    is involved internally, e.g: REPLACE(a,b,c)
-    - convert to @@character_set_connection if all arguments are numbers
-    - disallow DERIVATION_NONE
-  */
-  bool agg_arg_charsets_for_string_result_with_comparison(DTCollation &c,
-                                                          Item **items,
-                                                          uint nitems,
-                                                          int item_sep= 1)
-  {
-    return agg_item_charsets_for_string_result_with_comparison(c, func_name(),
-                                                               items, nitems,
-                                                               item_sep);
-  }
   Item *transform(THD *thd, Item_transformer transformer, uchar *arg);
   Item* compile(THD *thd, Item_analyzer analyzer, uchar **arg_p,
                 Item_transformer transformer, uchar *arg_t);

sql/item_sum.cc

@@ -3448,8 +3448,8 @@ Item_func_group_concat::fix_fields(THD *thd, Item **ref)
   }
 
   /* skip charset aggregation for order columns */
-  if (agg_item_charsets_for_string_result(collation, func_name(),
+  if (agg_arg_charsets_for_string_result(collation,
-                                          args, arg_count - arg_count_order))
+                                         args, arg_count - arg_count_order))
     return 1;
 
   result.set_charset(collation.collation);