Removed some old #if MYSQL_VERSION

- Removed never used warning that explicit_defaults_for_timestamp was
  not set

sql/item_timefunc.cc

@@ -3232,13 +3232,7 @@ void Item_func_str_to_date::fix_length_and_dec()
   if (agg_arg_charsets(collation, args, 2, MY_COLL_ALLOW_CONV, 1))
     return;
   if (collation.collation->mbminlen > 1)
-  {
-#if MYSQL_VERSION_ID > 50500
     internal_charset= &my_charset_utf8mb4_general_ci;
-#else
-    internal_charset= &my_charset_utf8_general_ci;
-#endif
-  }
 
   maybe_null= true;
   set_handler(&type_handler_datetime2);

sql/mysqld.cc

@@ -9680,17 +9680,6 @@ static int get_options(int *argc_ptr, char ***argv_ptr)
                       global_system_variables.max_allowed_packet);
   }
 
-#if MYSQL_VERSION_ID > 101001
-  /*
-    TIMESTAMP columns get implicit DEFAULT values when
-    --explicit_defaults_for_timestamp is not set.
-  */
-  if (!opt_help && !opt_explicit_defaults_for_timestamp)
-    sql_print_warning("TIMESTAMP with implicit DEFAULT value is deprecated. "
-                      "Please use --explicit_defaults_for_timestamp server "
-                      "option (see documentation for more details).");
-#endif
-
   if (log_error_file_ptr != disabled_my_option)
     opt_error_log= 1;
   else

sql/sql_show.cc

@@ -1076,13 +1076,7 @@ find_files(THD *thd, Dynamic_array<LEX_CSTRING*> *files, LEX_CSTRING *db,
     if (ha_discover_table_names(thd, db, dirp, &tl, false))
       goto err;
   }
-#if MYSQL_VERSION_ID < 100300
-  /* incomplete optimization, but a less drastic change in GA version */
-  if (!thd->lex->select_lex.order_list.elements &&
-      !thd->lex->select_lex.group_list.elements)
-#else
   if (is_show_command(thd))
-#endif
     tl.sort();
 #ifndef DBUG_OFF
   else

sql/table.cc

@@ -3770,17 +3770,6 @@ void append_unescaped(String *res, const char *pos, size_t length)
 
   for (; pos != end ; pos++)
   {
-#if defined(USE_MB) && MYSQL_VERSION_ID < 40100
-    uint mblen;
-    if (use_mb(default_charset_info) &&
-        (mblen= my_ismbchar(default_charset_info, pos, end)))
-    {
-      res->append(pos, mblen);
-      pos+= mblen;
-      continue;
-    }
-#endif
-
     switch (*pos) {
     case 0:				/* Must be escaped for 'mysql' */
       res->append('\\');