Fix inserting references list while selecting another kind of node

There are two ways dialogs determine if they are inserting or updating.

1. They evaluate whether the dialog is inserting or not and set a boolean
   flag, used later to steer the saving code

2. They evaluate whether the dialog is inserting or not and, if not,
   store the node to be updated in a property, used later to steer the
   saving code

In the reference list dialog, setup used strategy 1, and teardown used
strategy 2. We've now normalized to use strategy 2 in both methods, which
fixes this bug.

Bug: 61885
Change-Id: I1b077b2aef4121328bce2b373874dd7373e405a1