merge of 5.1-main into 5.1-maria. Myisam->Maria change propagation will follow.

There were so many changes into mtr (this is the new mtr coming) that I rather
copied mtr from 6.0-main here (at least this one knows how to run Maria tests).
I also fixed suite/maria tests to be accepted by the new mtr.

mysys/thr_mutex.c:
  adding DBUG_PRINT here, so that we can locate where the warning is issued.

mysql-test/include/wait_until_disconnected.inc

@@ -1,24 +1,24 @@
 #
-# Include this script after a shutdown to wait until the connection
-# to the server has been lost or timeout occurs.
-# When you change this file you may have to chance its cousin
-# wait_until_connected_again.inc
-
+# Include this script to wait until the connection to the
+# server has been dropped.
 --disable_result_log
 --disable_query_log
-let $counter= 5000;
+let $counter= 600;
 let $mysql_errno= 0;
 while (!$mysql_errno)
 {
-  --error 0,2002,2003,2006,1053
+  # Strangely enough, the server might return "Too many connections"
+  # while being shutdown, thus 1040 is an "allowed" error.
+  # See BUG#36228.
+  --error 0,1040,1053,2002,2003,2006,2013
   show status;
 
   dec $counter;
   if (!$counter)
   {
-    --die Server failed to disconnect me
+    --die Server failed to dissapear
   }
-  --sleep 0.1
+  --real_sleep 0.1
 }
 --enable_query_log
 --enable_result_log