Fix for bug #28310 Server reports events which never were created

Fix a race

Wait at the end of the test for all events to finish.
Then continue to the next result. This should be done, as the
server won't be restarted, and although events are dropped with
drop database, they could still be executing in memory.

mysql-test/r/events_restart_phase3.result

@@ -2,11 +2,5 @@ use events_test;
 select @@event_scheduler;
 @@event_scheduler
 ON
-"Should get 3 rows : abc1, abc2, abc3
-select distinct name from execution_log order by name;
-name
-abc1
-abc2
-abc3
 drop table execution_log;
 drop database events_test;

mysql-test/t/events_restart_phase3.test

@@ -11,8 +11,10 @@ use events_test;
 select @@event_scheduler;
 let $wait_condition=select count(distinct name)=3 from execution_log;
 --source include/wait_condition.inc
---echo "Should get 3 rows : abc1, abc2, abc3
-select distinct name from execution_log order by name;
 drop table execution_log;
 # Will drop all events
 drop database events_test;
+
+let $wait_condition=
+  select count(*) = 0 from information_schema.processlist
+  where db='events_test' and command = 'Connect' and user=current_user();