[CSSWG][css-cascade-4] Updated CR of CSS Cascading and Inheritance L4

The CSS WG has published an updated Candidate Recommendation of the
CSS Cascading and Inheritance Module Level 4:

     https://www.w3.org/TR/css-cascade-4/

This CSS module describes how to collate style rules and assign values
to all properties on all elements by way of cascading (choosing a
winning declaration among many) and inheritance (propagating values
from parent to child).

Aside from the same clarifications applied to the css-cascade-3 update
and dropping the obsolete/unimplemented “override” origin from DOM2STYLE,
the Level 4 update also:
   * Adds definitions for CSS property aliasing.
       https://www.w3.org/TR/css-cascade-4/#aliasing
   * Defines property value computation for text nodes,
     which is now observable due to 'display: contents'.
       https://www.w3.org/TR/css-cascade-4/#change-2016-text
A full list of changes is available at:
   https://www.w3.org/TR/2018/CR-css-cascade-4-20180828/#changes

Disposition of comments:
   https://drafts.csswg.org/css-cascade-3/issues-cr-2016
   https://drafts.csswg.org/css-cascade-4/issues-cr-2016

Please review the draft, and send any comments to this mailing list,
<www-style@w3.org>, prefixed with [css-cascade-3] (as I did on this
message) or (preferably) file them in the GitHub repository at
   https://github.com/w3c/csswg-drafts/issues

For the CSS WG,
~fantasai