Unnamed repository; edit this file 'description' to name the repository.
Auto merge of #147423 - nnethercote:DepNodeColor-tweaks, r=cjgillot
`DepNodeColor` tweaks
A follow-up to rust-lang/rust#147293, where I attempted and mostly failed to make things faster again, but I found a few cleanups worth doing.
r? `@saethlin`
