Default for &Path

[clarfonthey]

This was separated from #40009.

This has precedence due to the fact that PathBuf and Box<Path> already implement Default.

[rust-highfive]

r? @brson

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[alexcrichton]

We discussed this during libs triage today and the conclusion was that due to the surprising semantics of Path::new("") we'd prefer to avoid this implementation for now, so I'm going to close this.

@clarcharr we also consider the addition of Default for Box<Path> to be an accidental mistake (we didn't mean to let that through), would you mind sending a PR to remove it?

[aturon]

Oops, I saw @alexcrichton's comment too late, and already submitted a PR to remove the existing impl.