adds a field to the list of unstructed information. This list allows rendering objects
to add information that is specific to them (e.g. for an ILayoutController
the list of registered Control instances). These objects do not fit in one
of the other buckets of information and are therefore added to this list.
Parameters:
field - an entry for the renderer-specific information for this RenderObjectData,
must not be null
a List implementation that only contains objects that
implement the IField interface. The list will not contain
null elements. The ordering of the list might be changed between calls.
the status for this info object. The default return value should be
Status.OK. It should be changed to a different severity, if an added field
indicates some problem. Must not return null.