'MAX_BINLOG_CACHE_SIZE' ERROR
      
Problem:
=======
MySQL returns following error in win64.
"ERROR 1197 (HY000): Multi-statement transaction required more than
'max_binlog_cache_size' bytes of storage; increase this mysqld variable
and try again" when user tries to load >4G file even if
max_binlog_cache_size set to maximum value. On Linux everything
works fine.
      
Analysis:
========
The `max_binlog_cache_size' variable is of type `ulonglong'.  This
value is set to `ULONGLONG_MAX' at the time of server start up. The
above value is stored in an intermediate variable named
`saved_max_binlog_cache_size' which is of type `ulong'. In visual
c++ complier the `ulong' type is of 4bytes in size and hence the value
is getting truncated to '4GB' and the cache is not able to grow beyond
4GB size. The same limitation is observed with 
"max_binlog_stmt_cache_size" as well. Similar fix has been applied.
      
Fix:
===
As part of fix the type "ulong" is replaced with "my_off_t" which is of
type "ulonglong". 

mysys/mf_iocache.c:
  Added debug statement to simulate a scenario where the cache
  file's current position is set to >4GB
sql/log.cc:
  Replaced the type of `saved_max_binlog_cache_size' from "ulong" to
  "my_off_t", which is a type def for "ulonglong".