Take advantage of the new /*line*/ comments.

Fixes #26745

Change-Id: I8098642e0f11f7418fe81b9a08dbe07671f930fe
Reviewed-on: https://go-review.googlesource.com/c/151598
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>