Updating a SwTxtInputFld requires expanding the contents of the node.

Expanding the contents of the node requires all the positions of fields in the
node to be correct in order to expand them to the right place.

So on updating a SwTxtNode wait until all the attributes positions are adjusted
to be correct before expanding the SwTxtInputFlds in that node

Change-Id: I76500239a103e56be412707a708a303a58236070