x/net/html/atom: add "acronym" to 'extra' in gen.go

[16th-earl]

What version of Go are you using (go version)?

go version go1.9.2 darwin/amd64

Does this issue reproduce with the latest release?

yes

What operating system and processor architecture are you using (go env)?

darwin/amd64

What did you do?

import "golang.org/x/net/html/atom"
atom.Acronym

What did you expect to see?

Though the tag is deprecated in HTML5, it was commonly used in HTML4 and XHTML1. It should be one of 'extra' atom types, in the same way that atom.Strike and atom.Tt are still included.

What did you see instead?

undefined: atom.Acronym

[namusyaka]

The x/net/html package implements an HTML5-compliant tokenizer and parser.
This package does not seem to officially support html-4 and xhtml.

[rsc]

/cc @nigeltao

[gopherbot]

Change https://golang.org/cl/91315 mentions this issue: html/atom: add atom.Acronym