MDEV-532: Fix some race conditions in test cases.

With MDEV-532, the binlog_checkpoint event is logged asynchronously
from a binlog background thread. This causes some sporadic failures
in some test cases whose output depends on order of events in
binlog.

Fix using an include file that waits until the binlog checkpoint
event has been logged before proceeding with the test case.

mysql-test/extra/rpl_tests/rpl_insert_delayed.test

@@ -94,8 +94,10 @@ if  (`SELECT @@global.binlog_format = 'STATEMENT'`)
   #flush the logs before the test
   connection slave;
   FLUSH LOGS;
+  source include/wait_for_binlog_checkpoint.inc;
   connection master;
   FLUSH LOGS;
+  source include/wait_for_binlog_checkpoint.inc;
 }
 
 CREATE TABLE t1(a int, UNIQUE(a));

mysql-test/extra/rpl_tests/rpl_log.test

@@ -43,6 +43,7 @@ let $binlog_limit= 1,4;
 source include/show_binlog_events.inc;
 let $binlog_limit=;
 flush logs;
+--source include/wait_for_binlog_checkpoint.inc
 
 # We need an extra update before doing save_master_pos.
 # Otherwise, an unlikely scenario may occur:

mysql-test/extra/rpl_tests/rpl_show_relaylog_events.inc

@@ -41,8 +41,10 @@ INSERT INTO t1 VALUES (3);
 #
 
 FLUSH LOGS;
+--source include/wait_for_binlog_checkpoint.inc
 -- connection master
 FLUSH LOGS;
+--source include/wait_for_binlog_checkpoint.inc
 DROP TABLE t1;
 
 --let $is_relay_log= 0

mysql-test/include/wait_for_binlog_checkpoint.inc

@@ -0,0 +1,53 @@
+# include/wait_for_binlog_checkpoint.inc
+#
+# SUMMARY
+#
+#    Wait until binlog checkpoint has been logged for current binlog file.
+#    This is useful to avoid races with output difference for binlog
+#    checkpoints, as these are logged asynchronously from the binlog
+#    background thread.
+#
+# USAGE:
+#
+#    --source include/wait_for_binlog_checkpoint.inc
+
+let $_wait_count= 300;
+
+let $_found= 0;
+
+while ($_wait_count)
+{
+  dec $_wait_count;
+  let $_cur_binlog= query_get_value(SHOW MASTER STATUS, File, 1);
+  let $_more= 1;
+  let $_row= 1;
+  while ($_more)
+  {
+    let $_event= query_get_value(SHOW BINLOG EVENTS IN "$_cur_binlog", Event_type, $_row);
+    if ($_event == "No such row")
+    {
+      let $_more= 0;
+    }
+    if ($_event == "Binlog_checkpoint")
+    {
+      let $_info= query_get_value(SHOW BINLOG EVENTS IN "$_cur_binlog", Info, $_row);
+      if (`SELECT INSTR("$_info", "$_cur_binlog") != 0`)
+      {
+        let $_more= 0;
+        let $_wait_count= 0;
+        let $_found= 1;
+      }
+    }
+    inc $_row;
+  }
+  if ($_wait_count)
+  {
+    real_sleep 0.1;
+  }
+}
+
+if (!$_found)
+{
+  eval SHOW BINLOG EVENTS IN "$_cur_binlog";
+  --die ERROR: failed while waiting for binlog checkpoint $_cur_binlog
+}

mysql-test/suite/innodb/t/binlog_consistent.test

@@ -72,6 +72,7 @@ connection con3;
 --echo # Connection con3
 COMMIT;
 FLUSH LOGS;
+--source include/wait_for_binlog_checkpoint.inc
 
 connection default;
 --echo # Connection default

mysql-test/suite/multi_source/multisource.test

@@ -169,6 +169,7 @@ select * from db2.t1;
 
 --connection master1
 flush logs;
+--source include/wait_for_binlog_checkpoint.inc
 --save_master_pos
 --connection slave
 --sync_with_master 0, 'master1'