[Vault Dialog] Hide all elements (files and folders) if root folder is removed from sync

[bakkdoor]

Right now you can collapse folders to hide their elements, but even if a root folder is removed from sync with all its sub-folders, the file selector still shows all the un-synced folder's sub folders. I think it would be clearer to just remove them from the view at that point. Only show them back if the root folder is re-added to sync. Generally I think when collapsing a folder, we should also hide all sub folders and not just the files.

Any opinions?