Fix the passing of fields in filters
While updating the user's guide, I noticed a couple of minor problems
with how filters map fields. First, if a filter was using
CreateResultCoordinateSystem, it did not respect the
PassCoordinateSystems flag. Second, if both an initializer_list and
a mode was given to SetFieldsToPass, the mode was captured
incorrectly. Both problems are corrected.
Backport: release