Merge r328:340 from branches/5.0:

r340: Fix http://bugs.mysql.com/bug.php?id=18283 in ha_innodb.cc and
http://bugs.mysql.com/bug.php?id=18238 in InnoDB

r339: Remove disk space leak on update of BLOB columns (Bug #18252).

btr_cur_pessimistic_update(): Invoke rec_get_offsets() after
rec_set_field_extern_bits().

btr_store_big_rec_extern_fields(): Note that offsets will no longer be
valid after calling this function.

r338: Fix bug 18238 : check in pessimistic insert and update if the buffer
pool is exhausted by locks

row/row0upd.c

@@ -28,6 +28,7 @@ Created 12/27/1996 Heikki Tuuri
 #include "log0log.h"
 #include "pars0sym.h"
 #include "eval0eval.h"
+#include "buf0lru.h"
 
 
 /* What kind of latch and lock can we assume when the control comes to
@@ -1541,6 +1542,10 @@ row_upd_clust_rec(
 		return(err);
 	}
 
+	if (buf_LRU_buf_pool_running_out()) {
+
+		return(DB_LOCK_TABLE_FULL);
+	}
 	/* We may have to modify the tree structure: do a pessimistic descent
 	down the index tree */