[css-scoping] Give an English name to the >>> combinator.

Author: tabatkins

css-scoping/Overview.bs

@@ -493,7 +493,9 @@ Selecting Shadow-Projected Content: the ''::content'' pseudo-element</h4>
 <h4 id='deep-combinator'>
 Selecting Through Shadows: the ''>>>'' combinator</h4>
 
-	When a <dfn selector>>>></dfn> combinator is encountered in a selector,
+	When a <dfn selector>>>></dfn> combinator
+	(or <dfn export>shadow-piercing descendant combinator</dfn>)
+	is encountered in a selector,
 	replace every element in the <a>selector match list</a>
 	with every element reachable from the original element
 	by traversing any number of child lists or shadow trees.

css-scoping/Overview.html

@@ -1018,7 +1018,9 @@ <h4 class="heading settled" data-level="3.2.4" id="deep-combinator"><span class=
 
 
 
-      <p>When a <dfn class="css" data-dfn-type="selector" data-export="" id="selectordef-">>>><a class="self-link" href="#selectordef-"></a></dfn> combinator is encountered in a selector,
+      <p>When a <dfn class="css" data-dfn-type="selector" data-export="" id="selectordef-">>>><a class="self-link" href="#selectordef-"></a></dfn> combinator
+	(or <dfn data-dfn-type="dfn" data-export="" id="shadow-piercing-descendant-combinator">shadow-piercing descendant combinator<a class="self-link" href="#shadow-piercing-descendant-combinator"></a></dfn>)
+	is encountered in a selector,
 	replace every element in the <a data-link-type="dfn" href="http://dev.w3.org/csswg/selectors-4/#selector-match-list">selector match list</a>
 	with every element reachable from the original element
 	by traversing any number of child lists or shadow trees.</p>
@@ -1709,6 +1711,7 @@ <h2 class="no-num heading settled" id="index"><span class="content">Index</span>
       <li>@scope, <a href="#at-ruledef-scope" title="section 2.1.2">2.1.2</a></li>
       <li>::shadow, <a href="#selectordef-shadow" title="section 3.2.2">3.2.2</a></li>
       <li>shadow host, <a href="#shadow-host" title="section 3">3</a></li>
+      <li>shadow-piercing descendant combinator, <a href="#shadow-piercing-descendant-combinator" title="section 3.2.4">3.2.4</a></li>
       <li>shadow root, <a href="#shadow-root" title="section 3">3</a></li>
       <li>shadow tree, <a href="#shadow-tree" title="section 3">3</a></li>
       <li>top-level element, <a href="#top-level-element" title="section 3">3</a></li>