Fixed unlikely bug in the range optimzer when using many IN() queries on different key parts. (Bug #4157)


mysql-test/r/range.result:
  Test of range optimizer bug
mysql-test/t/range.test:
  Test of range optimizer bug
sql/opt_range.cc:
  Fixed unlikely bug in the range optimzer when using many IN() queries on
  different key parts. (Bug #4157)