Reload button on subsequent builds is not cached when the very first build has been canceled or it has raised an exception

[Mic92]

Consider this: Cancel/Exception -> 1. Retry -> 2. Retry

The second retry will check the build that was canceled or throw an exception instead of looking at 1. Retry,
since those build won't have any eval information cached, evaluation cannot be read from a cache.

[Mic92]

We also don't do gcroots for derivations, when re-using the cached evals, which might be an issue.