(Bug #4035 GROUP_CONCAT with HAVING clause truncates field                       
Bug #4057 LEFT() function in HAVING clause truncates query result).


mysql-test/r/func_gconcat.result:
  a test case
  Bug #4035 GROUP_CONCAT with HAVING clause truncates field                       
  Bug #4057 LEFT() function in HAVING clause truncates query result
mysql-test/t/func_gconcat.test:
  a test case
  Bug #4035 GROUP_CONCAT with HAVING clause truncates field                       
  Bug #4057 LEFT() function in HAVING clause truncates query result
sql/item_strfunc.cc:
  a fix (Bug #4057 LEFT() function in HAVING clause truncates query result)
sql/item_strfunc.h:
  a fix (Bug #4057 LEFT() function in HAVING clause truncates query result)
sql/item_sum.cc:
  a fix (Bug #4035 GROUP_CONCAT with HAVING clause truncates field)
sql/item_sum.h:
  a fix (Bug #4035 GROUP_CONCAT with HAVING clause truncates field)