The only thing gained by this method being non-static was access to
the instance's type parameter. In most cases this was not even
providing any additional safety, e.g. the ChangeQueryBuilder methods
already specify Predicate<ChangeData> in their signature so the type
can get picked up from there.
This was problematic for callers that might not have access to a
ChangeQueryBuilder instance, since that requires a CurrentUser.
Change-Id: I6b930e9aa4cce66203c7a2352b82bfd0b1cc26cd
30b280d309