The problem is that since MyISAM's concurrent_insert is on by
default some concurrent SELECT statements might not see changes
made by INSERT statements in other connections, even if the
INSERT statement has returned.

The solution is to disable concurrent_insert so that INSERT
statements returns after the data is actually visible to other
statements.


mysql-test/r/client_xml.result:
  Update test case result.
mysql-test/r/federated.result:
  Update test case result.
mysql-test/r/federated_bug_25714.result:
  Update test case result.
mysql-test/t/client_xml.test:
  Disable concurrent insert and restore old value at the
  end of the test so it doesn't affect other tests.
mysql-test/t/federated.test:
  Disable concurrent insert and restore old value at the
  end of the test so it doesn't affect other tests.
mysql-test/t/federated_bug_25714.test:
  Disable concurrent insert and restore old value at the
  end of the test so it doesn't affect other tests.