problems are located in the sql_partition.cc where functions calculation
    partition_id don't expect error returned from item->val_int().
    Fixed by adding checks to these functions.
    Note  - it tries to fix more problems than just the reported bug.
      
per-file comments:
modified:
  mysql-test/r/partition.result
    Bug#38083 Error-causing row inserted into partitioned table despite error
        test result
  mysql-test/t/partition.test
    Bug#38083 Error-causing row inserted into partitioned table despite error
        test case
  sql/opt_range.cc
    Bug#38083 Error-causing row inserted into partitioned table despite error
        get_part_id() call fixed
  sql/partition_info.h
    Bug#38083 Error-causing row inserted into partitioned table despite error
        get_subpart_id_func interface changed. 
  sql/sql_partition.cc
    Bug#38083 Error-causing row inserted into partitioned table despite error
        various functions calculationg partition_id and subpart_id didn't expect
            an error returned from item->val_int().  Error checks added.