Support new size values for width and height

[ausi]

Parent elements using width: fit-content should be skipped for example. Currently they can result in the circularity issue.

[ausi]

This should be postponed until more browsers support these keywords. Implementing it now would decrease performance (because it needs the original style of the element) with little to no benefit.

Code for cq-prolyfill.js:1064:

var originalStyle = getOriginalStyle(element, prop);

// max-content, min-content and fit-content including prefixed versions
if (originalStyle && originalStyle.substr(-8) === '-content') {
	return true;
}