Bug#27438 rpl_rotate_logs fails on Windows

 - Fix test case to work also when filesystem time differs
   from mysqld' time. I.e when running with data files on a
   network share.


mysql-test/r/rpl_rotate_logs.result:
  Update result file
mysql-test/t/rpl_rotate_logs.test:
  Calculate time to use in "purge master logs before" by taking
  last modification time of t2 and adding 1 second
  This is done in order to handle the case where file system time differs
  from mysqld's time

mysql-test/r/rpl_rotate_logs.result

@@ -50,7 +50,10 @@ show binary logs;
 Log_name	File_size
 master-bin.000002	363
 master-bin.000003	407
-purge master logs before now();
+select @time_for_purge:=DATE_ADD(UPDATE_TIME, INTERVAL 1 SECOND)
+from information_schema.tables
+where TABLE_SCHEMA="test" and TABLE_NAME="t2";
+purge master logs before (@time_for_purge);
 show binary logs;
 Log_name	File_size
 master-bin.000003	407

mysql-test/t/rpl_rotate_logs.test

@@ -107,9 +107,18 @@ show master logs;
 # we just tests if synonyms are accepted
 purge binary logs to 'master-bin.000002';
 show binary logs;
-# sleeping 10 seconds or more would make the slave believe connection is down
---real_sleep 1
-purge master logs before now();
+
+# Calculate time to use in "purge master logs before" by taking
+# last modification time of t2 and adding 1 second
+# This is donw in order to handle the case where file system
+# time differs from mysqld's time
+--disable_result_log
+select @time_for_purge:=DATE_ADD(UPDATE_TIME, INTERVAL 1 SECOND)
+  from information_schema.tables
+    where TABLE_SCHEMA="test" and TABLE_NAME="t2";
+--enable_result_log
+
+purge master logs before (@time_for_purge);
 show binary logs;
 insert into t2 values (65);
 sync_slave_with_master;