random slave crash on master crash + restart

[Patrick Crews]

When running the randgen test for master crash + recovery, we are seeing random instances where the slave crashes.
This occurs ~1 in 20 times and I have seen several different stack traces for this.

To repeat: ./dbqp --mode=randgen --randgen-path=/path/to/randgen --suite=slave_plugin multi_thread1_crash_recover --repeat=20

Backtrace:
110411 13:43:29 - drizzled got signal 6;
This could be because you hit a bug. It is also possible that this binary
 or one of the libraries it was linked against is corrupt, improperly built,
 or misconfigured. This error can also be caused by malfunctioning hardware.
We will try our best to scrape up some info that will hopefully help diagnose
the problem, but since we have already crashed, something is definitely wrong
and this may fail.

read_buffer_size=131072
max_used_connections=2
connection_count=2
It is possible that drizzled could use up to
(read_buffer_size + sort_buffer_size)*thread_count
bytes of memory
Hope that's ok; if not, decrease some variables in the equation.

Number of stack frames obtained: 26
/drizzle/drizzled/.libs/lt-drizzled() [0x6b3b0c]
()
gsignal()
abort()
()
()
cfree()
__gnu_cxx::new_allocator<char>::deallocate(char*, unsigned long)
std::_Vector_base<char, std::allocator<char> >::_M_deallocate(char*, unsigned long)
std::_Vector_base<char, std::allocator<char> >::~_Vector_base()
/drizzle/drizzled/.libs/lt-drizzled() [0x50a1e5]
__gnu_cxx::new_allocator<std::vector<char, std::allocator<char> > >::destroy(std::vector<char, std::allocator<char> >*)
/drizzle/drizzled/.libs/lt-drizzled() [0x5484da]
std::queue<std::vector<char, std::allocator<char> >, std::deque<std::vector<char, std::allocator<char> >, std::allocator<std::vector<char, std::allocator<char> > > > >::pop()
/drizzle/drizzled/.libs/lt-drizzled() [0x5459ee]
drizzled::Session::executeStatement()
drizzled::Session::run()
()
()
()
()
()
thread_proxy()
()
clone()

[Patrick Crews (patrick-crews)]

NOTE: this has been detected in trunk. Need to retest against elliott to make certain it is present there. including elliott as a target / will update accordingly when finished