API for Retrieving ALL Hierarchy Filters

We are using the Javascript API to read a hierarchy filter and observed that this API doesn't support retrieving all the filters (checked and unchecked) in the hierarchy at once. We have to get checked and unchecked filters separately where unchecked filter response doesn't contain the children of the unchecked node which is required to re-create the hierarchy in UI. Is this how this API is intended to work?

This is required if we enable 'Remember personalized view for each web client user' setting so that user's last state of filters (which we have a control for outside of the Web Player iframe) can be rendered in UI for future user sessions.

Originall discussed in case # 01801413