keep vio from being freed twice when we are low on memory
mysys/safemalloc.c
changes for --safemalloc-mem-limit
sql/mini_client.cc
keep vio from being freed twice
sql/mysqld.cc
changes for --safemalloc-mem-limit
sql/slave.cc
prevent closing connection twice
sql/sql_string.h
shrink() did not work right when my_realloc() failed