[giowr] (2) Mention that for rel=icon UAs should also use type=''; me…

…ntion what to do when an icon sucks; mention how to handle missing sizes=''.

git-svn-id: http://svn.whatwg.org/webapps@1713 340c8d12-0b0e-0410-8428-c7bf67bfef74

index

  <p>Icons could be auditory icons, visual icons, or other kinds of icons. If
   multiple icons are provided, the user agent must select the most
   appropriate icon according to the <code title=attr-link-media><a
   href="#media0">media</a></code> and <code title=attr-link-sizes><a
   appropriate icon according to the <code title=attr-link-type><a
   href="#type">type</a></code>, <code title=attr-link-media><a
   href="#media0">media</a></code>, and <code title=attr-link-sizes><a
   href="#sizes0">sizes</a></code> attributes. If there are multiple equally
   appropriate icons, user agents must use the last one declared in <a
   href="#tree-order">tree order</a>.
   href="#tree-order">tree order</a>. If the user agent tries to use an icon
   but that icon is determined, upon closer examination, to in fact be
   inappropriate (e.g. because it uses an unsupported format), then the user
   agent must try the next-most-appropriate icon as determined by the
   attributes.

  <p>There is no default type for resources given by the <code
   title=rel-icon><a href="#icon3">icon</a></code> keyword.</p>
   href="#sizes0">sizes</a></code> attribute must not represent icon sizes
   that are not actually available in the linked resource.

  <p>If the attribute is not specified, then the user agent must assume that
   the given icon is appropriate, but less appropriate than an icon of a
   known and appropriate size.

  <div class=example>
   <p>The following snippet shows the top part of an application with several
    icons.</p>

source

  <p>Icons could be auditory icons, visual icons, or other kinds of
  icons. If multiple icons are provided, the user agent must select
  the most appropriate icon according to the <code
  title="attr-link-media">media</code> and <code
  title="attr-link-type">type</code>, <code
  title="attr-link-media">media</code>, and <code
  title="attr-link-sizes">sizes</code> attributes. If there are
  multiple equally appropriate icons, user agents must use the last
  one declared in <span>tree order</span>.</p>
  one declared in <span>tree order</span>. If the user agent tries to
  use an icon but that icon is determined, upon closer examination, to
  in fact be inappropriate (e.g. because it uses an unsupported
  format), then the user agent must try the next-most-appropriate icon
  as determined by the attributes.</p>

  <p>There is no default type for resources given by the <code
  title="rel-icon">icon</code> keyword.</p> <!-- XXX we don't define
  icon sizes that are not actually available in the linked
  resource.</p>

  <p>If the attribute is not specified, then the user agent must
  assume that the given icon is appropriate, but less appropriate than
  an icon of a known and appropriate size.</p>

  <div class="example">

   <p>The following snippet shows the top part of an application with