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>