The Create UI is not validating the parent field after using the tree picker to select it.

How to reproduce:

1. Add a template provider that has an 'allowed spaces' restriction on it
2. Select the template provider in the create UI (in a location where that template provider is usable from, i.e. visible in the list) and press the location edit button.
3. Input a random location that generates an error because it is no tin the list of allowed spaces.
4. Input a good location that is in the list of allowed spaces and see the error go away.
5. Repeat 3 to generate the error again
6. Use the tree picker to select a good location that should make the error go away
7. Observe that the error is still there, even if the selected location is good.

This is only a visual bug, since clicking on the parent input and then clicking outside it (to lose focus) or even submitting the form generates a new validation call and the selected (and correct) value will pass validation.