2015: add build tags for recent talks

This should make the build green for this repository.

Updates golang/go#11811

Change-Id: I0c2300586b77733876c2311e3d27e04965c2cbf0
Reviewed-on: https://go-review.googlesource.com/18626
Reviewed-by: Russ Cox <rsc@golang.org>
7 files changed