This change essentially reverts the change of July 2, which broke the feature to specify "editor=none". This is important for the "form" form-field entry, which requires a FORM tag, that is usually removed by actual version of the ckeditor.
In order to make the "editor=" formfield spec option have any effect, one should catch the value from the spec early, before the formfield is reclassed and initialized
This also exposes that the editor=none value is not valid (detected by xowiki and xowf automated tests). For this to be valid one should define it as a richtext subclass.