core used to have a test case that ran various Revision tests
with and without ContentHandlerUseDB set, however it did not
run due to the class / file having a bad name.
This patch reintroduces the running on Revision tests for both
ContentHandlerUseDB settings.
The global has to be set in setup / before the page used for
testing is created, else this page will be created with the
wrong values in the DB for use in the tests.
Change-Id: Ied1023e22eeac413fa86ea6946aa31619fd66319
