cargomedia/CM — pull request #1473 by vogdb (2014-11-13 08:23:28+00:00)
Title: Check return expectations of Form::getField

Followup from https://github.com/cargomedia/sk/pull/871

`getField` can currently return `null`, in many places that's not expected. Are there even places where we expect `null`?
I'd suggest to use a version that gives a meaningful error message when the field is expected to be around, wdyt?