[whatwg] definition of :link and :visited should allow flexibility

[L. David Baron]

http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#selector-link
says:
  # All a elements that have an href attribute, all area elements
  # that have an href attribute, and all link elements that have an
  # href attribute, must match one of :link and :visited.

A number of user agents have recently implemented changes to
handling of :link and :visited that can't be described strictly in
terms of an element matching a selector.  These are described in
more detail in http://dbaron.org/mozilla/visited-privacy .

css3-selectors has an exception that allows this:
  # UAs may therefore treat all links as unvisited links, or
  # implement other measures to preserve the user's privacy while
  # rendering visited and unvisited links differently. 
    --http://www.w3.org/TR/css3-selectors/#the-link-pseudo-classes-link-and-visited

HTML5 should have a similar exception that allows user agents to be
more flexible than requiring that all of the elements listed match
exactly one of :link and :visited.

-David

-- 
L. David Baron                                 http://dbaron.org/
Mozilla Corporation                       http://www.mozilla.com/