[css-text-decor-4] Add 'always' value to text-decoration-skip-ink. Fixes w3c#4277

Author: fantasai

css-text-decor-4/Overview.bs

@@ -1031,7 +1031,7 @@ Skipping Glyphs: the 'text-decoration-skip-ink' property</h4>
 
 	<pre class="propdef">
 	Name: text-decoration-skip-ink
-	Value: auto | none
+	Value: auto | none | always
 	Initial: ''auto''
 	Applies to: all elements
 	Inherited: yes
@@ -1049,10 +1049,10 @@ Skipping Glyphs: the 'text-decoration-skip-ink' property</h4>
 	The UA must also skip a small distance to either side of the glyph outline.
 
 	<div class="figure">
-		<p><img title="text-decoration-skip-ink: auto"
-		        alt="An alphabetic underline through Myanmar text skips around descenders and the vertical strokes of combining characters that drop below the alphabetic baseline."
-		        src="images/decoration-skip-ink.png">
-		<p class="caption">''text-decoration-skip-ink: auto''</p>
+		<img title="Skipping Descenders When Drawing an Underline"
+		     alt="An alphabetic underline through Myanmar text skips around descenders and the vertical strokes of combining characters that drop below the alphabetic baseline."
+		     src="images/decoration-skip-ink.png">
+		<p class="caption">Skipping Glyph Ink
 	</div>
 
 	<div class="issue">
@@ -1075,18 +1075,16 @@ Skipping Glyphs: the 'text-decoration-skip-ink' property</h4>
 			UAs <em>may</em> interrupt underlines and overlines
 			where the line would cross glyph ink
 			and to some distance to either side of the glyph outline.
-			Line-throughs must remain continuous, however.
 
-			<div class="figure">
-				<img title="Skipping Descenders When Drawing an Underline"
-				     alt="An alphabetic underline through Myanmar text skips around descenders and the vertical strokes of combining characters that drop below the alphabetic baseline."
-				     src="images/decoration-skip-ink.png">
-				<p class="caption">Skipping Glyph Ink
-			</div>
+		<dt><dfn value for="text-decoration-skip-ink">always</dfn></dt>
+		<dd>
+			UAs <em>must</em> interrupt underlines and overlines
+			where the line would cross glyph ink
+			and to some distance to either side of the glyph outline.
 
 		<dt><dfn value for="text-decoration-skip-ink">none</dfn></dt>
 		<dd>
-			UA must draw continuous lines,
+			UA must draw continuous underlines and overlines,
 			without interruptions when they cross over a glyph.
 	</dl>