[css-device-adapt] Cascade @Viewport with initial viewport for MQ.

Used to be "recommended". Made it a "must". Changed the wording a bit.

Author: Rune Lillesveen

css-device-adapt/Overview.html

@@ -1254,19 +1254,24 @@ <h2 id=media-queries><span class=secno>7. </span>Media Queries</h2>
     default aspect ratio of the user agent.”
   </blockquote>
 
-  <p>For <code class=css>@viewport</code> rules, though, it is recommended
-   that they are applied before media queries for other rules are evaluated.
+  <p>For <code class=css>@viewport</code> rules, though, the UA must cascade
+   them separately with the <a href="#initial-viewport">initial viewport</a>
+   size used for evaluating media feature expressions and other values that
+   depend on the viewport size to avoid circular dependencies, but use the
+   actual viewport size when cascading all other properties and descriptors.
 
-  <p>Recommended procedure for applying CSS rules:
+  <p>Procedure for applying CSS rules:
 
   <ol>
-   <li>Apply <code class=css>@viewport</code> rules. If <code
-    class=css>@viewport</code> rules rely on media queries, use the viewport
-    descriptors of the <a href="#initial-viewport">initial viewport</a>.
+   <li>Cascade all <code class=css>@viewport</code> rules using the <a
+    href="#initial-viewport">initial viewport</a> size for values and
+    evaluations which rely on viewport size
 
-   <li>Apply style rules. If style rules rely on media queries, use the
-    viewport descriptors obtained from step 1 when evaluating the media
-    queries.
+   <li>Compute the <a href="#actual-viewport">actual viewport</a> from the
+    cascaded viewport descriptors
+
+   <li>Cascade all other properties and descriptors using the <a
+    href="#actual-viewport">actual viewport</a> size
   </ol>
 
   <p class=note>The rationale for using the viewport descriptors obtained

css-device-adapt/Overview.src.html

@@ -1000,18 +1000,22 @@ <h2>Media Queries</h2>
       involving &lsquo;device-aspect-ratio&rsquo; will be based on the default aspect ratio
       of the user agent.&rdquo;</p></blockquote>
 
-    <p>For <code class="css">@viewport</code> rules, though, it is recommended
-      that they are applied before media queries for other rules are evaluated.</p>
+    <p>For <code class="css">@viewport</code> rules, though, the UA must cascade
+      them separately with the <span>initial viewport</span> size used for
+      evaluating media feature expressions and other values that depend on the
+      viewport size to avoid circular dependencies, but use the actual viewport
+      size when cascading all other properties and descriptors.</p>
 
-    <p>Recommended procedure for applying CSS rules:</p>
+    <p>Procedure for applying CSS rules:</p>
 
     <ol>
-      <li>Apply <code class="css">@viewport</code> rules. If
-	<code class="css">@viewport</code> rules rely on media queries, use
-	the viewport descriptors of the <span>initial viewport</span>.</li>
-      <li>Apply style rules. If style rules rely on media queries, use the
-	viewport descriptors obtained from step 1 when evaluating the media
-	queries.</li>
+      <li>Cascade all <code class="css">@viewport</code> rules using the
+        <span>initial viewport</span> size for values and evaluations which rely
+	on viewport size</li>
+      <li>Compute the <span>actual viewport</span> from the cascaded viewport
+        descriptors</li>
+      <li>Cascade all other properties and descriptors using the <span>actual
+        viewport</span> size</li>
     </ol>
 
     <p class="note">The rationale for using the viewport descriptors obtained from applying