User node rooting starts prior to setup completion

[mortoray]

This is a succesor to https://github.com/fusetools/fuselibs-public/issues/1096 The core issue is that Android (possibly iOS as well) root frame setup is not complete by the time we start rooting nodes. This can lead to some inneficiency in setup (though #1096 is believed to cover the most inefficient aspect). Things like window() can resolve the wrong value, or a temporary value.

It's not clear what the proper fix here is. We have some nodes like StatusBarConfig which probabyl should root prior to setup completiong, or maybe even some JavaScript nodes in the root, or the core Model. This issue is a reminder that something isn't quite right.