Merge with MySQL 5.1.55

- Fixed some issues with partitions and connection_string, which also fixed lp:716890 "Pre- and post-recovery crash in Aria"
- Fixed wrong assert in Aria

Now need to merge with latest xtradb before pushing 

sql/ha_partition.cc:
  Ensure that m_ordered_rec_buffer is not freed before close.
sql/mysqld.cc:
  Changed to use opt_stack_trace instead of opt_pstack.
  Removed references to pstack
sql/partition_element.h:
  Ensure that connect_string is initialized
storage/maria/ma_key_recover.c:
  Fixed wrong assert

mysql-test/suite/funcs_1/t/myisam_views-big.test

@@ -1,6 +1,9 @@
 #### suite/funcs_1/t/myisam_views.test
 
 --source include/no_valgrind_without_big.inc
+# because of a pair of slow Solaris Sparc machines in pb2,
+# this test is marked as big:
+--source include/big_test.inc
 
 # MyISAM tables should be used
 #