Closes#7306
We started noticing that when a `TextEditor` pane got split, the same view for
`Gutter` was being shared amongst several models, thereby making the same DOM
element accessible simultaneously by more than one object. This made us
experience *orphaned line numbers*, caused by two instances of
`LineNumberGutterComponent` mutating `.line-numbers` at the same time.
This is a typical race condition which I would normally address by understanding
and possibly locking the correct order in which operations should happen.
However, I believe in this situation we shouldn’t actually care about ordering
at all, since I think views should be kept “local”, thus avoiding to expose them
to the world and/or reusing them across other views (either accidentally as in
this case or on purpose).
b0d93accf7