fix field names when comparing to 'pre' data
This is very similar to !254 (merged).
Some fields have a different "canonical" and "unique" name. Contact fields have a field which is canonically named source
but has a unique name of contact_source
to differentiate from other source
fields.
CiviRules does comparisons using the canonical names. Data passed to civicrm_post
uses canonical names, so great.
But when we look up data with an API3 call, it returns unique names, and if we try to compare to one of those fields, it will return a NULL
value.
In !254 (merged) we dealt with fixing API3 calls on delayed actions. In this case, we are fixing API3 calls on the pre
data, which we get in part with an API3 call.