Bug#57306 SHOW PROCESSLIST does not display string literals well.

Problem: Extended characters outside of ASCII range where not displayed
properly in SHOW PROCESSLIST, because thd_info->query was always sent as 
system_character_set (utf8). This was wrong, because query buffer
is never converted to utf8 - it is always have client character set.

Fix: sending query buffer using query character set

  @ sql/sql_class.cc
  @ sql/sql_class.h
    Introducing a new class CSET_STRING, a LEX_STRING with character set.
    Adding set_query(&CSET_STRING)
    Adding reset_query(), to use instead of set_query(0, NULL).

  @ sql/event_data_objects.cc
    Using reset_query()

  @ sql/log_event.cc
    Using reset_query()
    Adding charset argument to set_query_and_id().

  @ sql/slave.cc
    Using reset_query().

  @ sql/sp_head.cc
    Changing backing up and restore code to use CSET_STRING.

  @ sql/sql_audit.h
    Using CSET_STRING.
    In the "else" branch it's OK not to use
    global_system_variables.character_set_client.
    &my_charset_latin1, which is set in constructor, is fine
    (verified with Sergey Vojtovich).

  @ sql/sql_insert.cc
    Using set_query() with proper character set: table_name is utf8.

  @ sql/sql_parse.cc
    Adding character set argument to set_query_and_id().
    (This is the main point where thd->charset() is stored
     into thd->query_string.cs, for use in "SHOW PROCESSLIST".)
    Using reset_query().
    
  @ sql/sql_prepare.cc
    Storing client character set into thd->query_string.cs.

  @ sql/sql_show.cc
    Using CSET_STRING to fetch and send charset-aware query information
    from threads.

  @ storage/myisam/ha_myisam.cc
    Using set_query() with proper character set: table_name is utf8.

  @ mysql-test/r/show_check.result
  @ mysql-test/t/show_check.test
    Adding tests

1 files changed, 2 insertions, 1 deletions

diff --git a/sql/sql_insert.cc b/sql/sql_insert.cc
index a81c9ae15a0..eaaf7901e25 100644
--- a/sql/sql_insert.cc
+++ b/sql/sql_insert.cc
@@ -2099,7 +2099,8 @@ bool delayed_get_table(THD *thd, TABLE_LIST *table_list)
       mysql_mutex_unlock(&LOCK_thread_count);
       di->thd.set_db(table_list->db, (uint) strlen(table_list->db));
       di->thd.set_query(my_strdup(table_list->table_name,
-                                  MYF(MY_WME | ME_FATALERROR)), 0);
+                                  MYF(MY_WME | ME_FATALERROR)),
+                        0, system_charset_info);
       if (di->thd.db == NULL || di->thd.query() == NULL)
       {
         /* The error is reported */