Merge r1067:1077 from branches/5.0:

innobase_start_or_create_for_mysql(): Remove unnecessary delay now that
we moved the setting sync_order_checks_on=TRUE to log0recv.c,
to the start of the rollback phase in crash recovery.

Fix assertion failure sync0sync.c line 1239
(the latter ut_error in sync_thread_reset_level())
in crash recovery when UNIV_SYNC_DEBUG is enabled.

log/log0recv.c

@@ -33,6 +33,7 @@ Created 9/20/1997 Heikki Tuuri
 #include "btr0cur.h"
 #include "dict0boot.h"
 #include "fil0fil.h"
+#include "sync0sync.h"
 
 #ifdef UNIV_HOTBACKUP
 /* This is set to FALSE if the backup was originally taken with the
@@ -2855,6 +2856,11 @@ recv_recovery_from_checkpoint_finish(void)
 #ifndef UNIV_LOG_DEBUG
 	recv_sys_free();
 #endif
+
+#ifdef UNIV_SYNC_DEBUG
+	/* Switch latching order checks on in sync0sync.c */
+	sync_order_checks_on = TRUE;
+#endif
 	if (srv_force_recovery < SRV_FORCE_NO_TRX_UNDO) {
 		/* Rollback the uncommitted transactions which have no user
 		session */

srv/srv0start.c

@@ -1601,17 +1601,6 @@ innobase_start_or_create_for_mysql(void)
 	srv_was_started = TRUE;
 	srv_is_being_started = FALSE;
 
-#ifdef UNIV_SYNC_DEBUG
-	/* Wait a while so that the created threads have time to suspend
-	themselves before we switch sync debugging on; otherwise a thread may
-	execute mutex_enter() before the checks are on, and mutex_exit() after
-	the checks are on, which will cause an assertion failure in sync
-	debug. */
-
-	os_thread_sleep(3000000);
-	sync_order_checks_on = TRUE;
-#endif
-
 	if (trx_doublewrite == NULL) {
 		/* Create the doublewrite buffer to a new tablespace */