This ensures more deeply-nested entries can be displayed without
needing to show scrollbars. Adding scrollbars introduces UX issues
when creating/renaming files because there are two scroll layers:
the outer project panel AND the editor.

Sublime Text and Atom dodged this issue by not displaying an inline
editor and showing it as a modal instead. VS Code shows the editor
inline but has a much more compact visualization. I think we should
copy VS Code.