Document change in addClass/removeClass for jQuery 3

[AurelioDeRosa]

jQuery 3 changes the behavior of addClass/removeClass for better SVG support. Thanks you @gibson042 for the feedback.

[dmethvin]

Something like this paragraph might work:

In HTML documents only, browsers keep the class attribute (e.g. $(elem).attr("class") or elem.getAttribute("class") and the className property (e.g. $(elem).prop("className") or elem.className) in sync; when you change one of them the browser updates the other. Prior to jQuery 3.0, jQuery used the className property in addClass and removeClass, which is not compatible with XML or SVG documents. As of jQuery 3.0, the class attribute is used instead and these methods can be used on XML or SVG.

[AurelioDeRosa]

Fixed with commit 4651f44.

[timmywil]

Will be added in 1.12/2.2. 9bf0ad3

[AurelioDeRosa]

Thank you for that @timmywil. Should I include it in the main branch once we release 1.12/2.2?

[timmywil]

Yup, I'm trying to get the branch to point where it can be merged on release.