The only file that really changed is
x/net/idna (upstream 8253218a).

See CL 73730: avoid memory leak in validation codes

The rest is just a small change in the
generation line at the top.

Change-Id: I62c5172f77f63d919c41d11c6db0a9517bc2a221
Reviewed-on: https://go-review.googlesource.com/74953Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>