with a testcase.
We needed to init_master_info before we flush_master_info
in LOAD DATA FROM MASTER.


mysql-test/r/rpl000009.result:
  result update
mysql-test/t/rpl000009.test:
  adding a test for RESET SLAVE + LOAD DATA FROM MASTER
sql/repl_failsafe.cc:
  LOAD DATA FROM MASTER udpates the master info in the slave,
  so needs to ensure that it is properly inited first
  (otherwise, after RESET SLAVE, we are flush_io_cache()ing
  an uninitialized IO_CACHE master.info).
  Note that it master info is already inited (active_mi->inited==1),
  init_master_info() will do nothing, which is what we want.