Remove problematic icon matching algorithm (#1120)

index.html

@@ -662,16 +662,6 @@ <h3>
  an <abbr title="Operating system">OS</abbr>'s task switcher and/or
  system preferences.
  </p>
- <p>
- If there are multiple equally appropriate images in
- [=manifest/icons=], a user agent MUST use the last one declared in
- order at the time that the user agent collected the list of
- [=manifest/icons=]. If the user agent tries to use an icon but that
- icon is determined, upon closer examination, to be inappropriate
- (e.g. because its content type is unsupported), then the user agent
- MUST try the next-most-appropriate icon as determined by examining
- the [=manifest image resource=]'s members.
- </p>
  <aside class="note">
  <p>
  When [=processing a manifest=], the [=process image resources=]
@@ -1660,7 +1650,11 @@ <h3>
  <dfn data-dfn-for="icon purpose">any</dfn> (default)
  </dt>
  <dd>
- The user agent is free to display the icon in any context.
+ The user agent is free to display the icon where no [=manifest
+ image resource/purpose=] is required. For example, a
+ [=manifest image resource=] with a "any" purpose 
+ wouldn't be used in a context where "[=icon purpose/monochrome=]" 
+ is required.
  </dd>
  </dl>
  <p>