Default box-sizing on <input type=color>

[zcorpan]

When writing tests for #4143 I noticed that the spec has box-sizing: border-box for buttons in general but not for <input type=color>.

http://software.hixie.ch/utilities/js/live-dom-viewer/saved/6501

WebKit/Chromium have border-box content-box, Gecko/EdgeHTML have content-box border-box.

I suggest we change it to border-box so it's consistent with other buttons.

[zcorpan]

WebKit/Chromium have border-box, Gecko/EdgeHTML have content-box.

This was the other way around.

[zcorpan]

https://bugs.chromium.org/p/chromium/issues/detail?id=962927
https://bugs.webkit.org/show_bug.cgi?id=197878

[zcorpan]

This was fixed by #4143