I added these notifies in #23011, but in practive have found them to be
overly disruptive. It would definitely be good to do something better
than logging here, but having a sticky error notification is worse. I
think it is still good to notify on mutation failures, so left those in

In particular with rust-analyzer, "Go to definition" and "Find
references" frequently fail with "Content modified" quite a while after
sending the request. Since users are probably used to these operations
being finicky it doesn't seem useful to have a prominent display of
errors for them.