[css-lists] Fix definition of list-style-position:outside to not reference position:marker.

Author: tabatkins

css-lists-3/Overview.bs

@@ -393,13 +393,29 @@ Positioning Markers: The 'list-style-position' property</h3>
 
 		<dt><dfn id='list-style-position-outside'>outside</dfn>
 		<dd>
-			The 'position' property on the marker computes to ''marker''.
-			Additionally, the base directionality of the marker
-			(used as an input to the bidi resolution algorithm)
-			must be taken from the marker's <a>marker positioning reference element</a>.
-
-			If the <a>list item</a> is <a>inline</a>,
-			this value instead computes to ''inside''.
+			If the <a>list item</a> is a <a>block container</a>:
+			the marker box is outside the principal block box;
+			however, the position of the list-item marker adjacent to floats is undefined.
+			CSS does not specify the precise location of the marker box
+			or its position in the painting order,
+			but does require that it be placed on the <a>inline-start</a> side of the box,
+			using the <a>writing mode</a> of the box indicated by 'marker-side'.
+			The marker box is fixed with respect to the principal block box's border
+			and does not scroll with the principal box's content.
+			A UA may hide the marker if the element's 'overflow' is other than ''overflow/visible''.
+			(This allowance may change in the future.)
+			The size or contents of the marker box may affect
+			the height of the principal block box
+			and/or the height of its first line box,
+			and in some cases may cause the creation of a new line box;
+			this interaction is also not defined.
+
+			Issue: This is handwavey nonsense from CSS2, and needs a real definition.
+
+			If the <a>list item</a> is an <a>inline box</a>:
+			this value is equivalent to ''inside''.
+
+			Issue: Alternatively, ''outside'' could lay out the marker as a previous sibling of the principal box.
 	</dl>
 
 	<div class=example>
@@ -1330,8 +1346,6 @@ Use <<custom-ident>> consistently for counter names.
 	<ol>
 		<li>The ''::marker'' pseudo-element has been introduced to allow styling of the list marker directly.
 
-		<li>The ''marker'' value for 'position' has been added, to allow elements in the document to position themselves similarly to how markers do.
-
 		<li>'list-style-type' now accepts a <<string>>.
 
 		<li>The list-item predefined counter identifier has been introduced.