runtime: eliminate a few usages of named return values in functions to make it consistent
runtime: eliminate a few usages of named return values in functions to make it consistent

Change-Id: Ia7d72b134a52627fd3c19a3c238fba8deb5e01c0
Reviewed-on: https://go-review.googlesource.com/c/go/+/407534
Reviewed-by: Michael Knyszek <4473450dc5c88f06e1fb787f303d7805ec2aee65@google.com>
Reviewed-by: Michael Pratt <e7f1edc6d5aa9f6c8c377425db8f1a5816cbbb88@google.com>

golang/go,golang/go,golang/go,golang/go,golang/go,golang/go,golang/go,golang/go