[css-regions] fix nested specified flow paragraph

Author: astearns

css-regions/Overview.html

@@ -735,9 +735,12 @@ <h3 id=the-flow-into-property><span class=secno>3.1. </span>The ‘<a
    boxes and is not displayed.
 
   <p>The children of an element or content with a specified flow may
-   themselves have a specified flow. If an element or content has the same
-   specified flow as one of its ancestors, it becomes the next sibling of its
-   closest ancestor with the same specified flow.
+   themselves have a specified flow, in which case they become the next
+   sibling of the latest element or content collected in that flow. In some
+   cases, the child can become the next sibling for one of its ancestors in
+   the same flow.
+
+  <p>
 
   <p>Content in a <a href="#named-flow0">named flow</a> is sequenced in
    document order. The visual formatting model uses the relationships between

css-regions/Overview.src.html

@@ -526,13 +526,13 @@ <h3 id="the-flow-into-property">The 'flow-into' property</h3>
 
     <p>The children of an element or content 
       with a specified flow 
-      may themselves have a specified flow. 
-      If an element or content has 
-      the same specified flow 
-      as one of its ancestors, 
-      it becomes the next sibling 
-      of its closest ancestor 
-      with the same specified flow.</p>
+      may themselves have a specified flow, 
+      in which case they become 
+      the next sibling of the latest element 
+      or content collected in that flow. 
+      In some cases, 
+      the child can become the next sibling 
+      for one of its ancestors in the same flow.<p>
 
     <p>Content in a <span>named flow</span> 
       is sequenced in document order.