log/slog: log and logAttrs initialize ctx at top
In extreme cases (e.g., ctx = nil), it is recommended to initialize the
context only once at the entry point before using log and logAttrs.
Change-Id: Ib191963f52183406d7fcd5104b60fea1a9e1bc80
GitHub-Last-Rev:
e1719b95390011a45a0a6652a13e675279bc76cd
GitHub-Pull-Request: golang/go#73066
Reviewed-on: https://go-review.googlesource.com/c/go/+/661255
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Jonathan Amsterdam <jba@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>