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

sql/sql_lex.h

@@ -1714,14 +1714,8 @@ typedef struct st_lex : public Query_tables_list
   bool verbose, no_write_to_binlog;
 
   bool tx_chain, tx_release;
-  /*
-    Special JOIN::prepare mode: changing of query is prohibited.
-    When creating a view, we need to just check its syntax omitting
-    any optimizations: afterwards definition of the view will be
-    reconstructed by means of ::print() methods and written to
-    to an .frm file. We need this definition to stay untouched.
-  */
-  bool view_prepare_mode;
+
+  uint8 context_analysis_only;
   bool safe_to_cache_query;
   bool subqueries, ignore;
   st_parsing_options parsing_options;
@@ -1842,6 +1836,13 @@ typedef struct st_lex : public Query_tables_list
     delete_dynamic(&plugins);
   }
 
+  inline bool is_ps_or_view_context_analysis()
+  {
+    return (context_analysis_only &
+            (CONTEXT_ANALYSIS_ONLY_PREPARE |
+             CONTEXT_ANALYSIS_ONLY_VIEW));
+  }
+
   inline void uncacheable(uint8 cause)
   {
     safe_to_cache_query= 0;