html: sync changes from x/net

[LukeShu]

Before 324513b (2012-01-04) std "html" and what is now
"golang.org/x/net/html" were the same. Ever since then (well, since
4e0749a (2012-05-29)) the escape/unescape code that they share has
been drifting apart, each receiving separate improvements.

This CL cherry-picks over all of the changes that "x/net/html" has
seen.

This is the counterpart to https://golang.org/cl/580855, and so also
includes the de-duplication requested at
https://go-review.googlesource.com/c/net/+/580855/comment/8f8679a3_12b9ead1/

4e0749a :

Author: Andrew Balholm <andybalholm@gmail.com> Date: Wed May 30 15:50:12 2012 +1000 exp/html: Convert \r and \r\n to \n when tokenizing Also escape "\r" as "&#13;" when rendering HTML. Pass 2 additional tests. R=nigeltao CC=golang-dev https://golang.org/cl/6260046 

golang/net@3d87fd6 :

Author: Dmitry Savintsev <dsavints@gmail.com> Date: Thu Feb 26 23:44:25 2015 +0100 x/net/html: Sync the html parser and atom with the current whatwg spec The current documentation as well as set of atoms and attributes has gotten slightly out of sync with the current state of the WHATWG html5 specification. The change adds and removes several of the atoms and attributes, updates the documentation (such as steps numbering in inBodyEndTagFormatting) and modifies the spec URLs to https:// Change-Id: I6dfa52785858c1521301b20b1e585e19a08b1e98 Reviewed-on: https://go-review.googlesource.com/6173 Reviewed-by: Nigel Tao <nigeltao@golang.org> 

[gopherbot]

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[gopherbot]

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Patch Set 1:

(1 comment)

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[gopherbot]

Message from Luke Shumaker:

Patch Set 1:

(2 comments)

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[gopherbot]

Message from Luke Shumaker:

Patch Set 1:

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Patch Set 1:

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Patch Set 1:

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Message from Damien Neil:

Patch Set 1:

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Patch Set 1:

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Patch Set 2:

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