[selectors-4] Exclude pseudo-elements from :has() and :nth-child() #7463 #8212

Author: fantasai

selectors-4/Overview.bs

@@ -1225,7 +1225,7 @@ The Specificity-adjustment Pseudo-class: '':where()''</h3>
 The Relational Pseudo-class: '':has()''</h3>
 
 	The relational pseudo-class, <dfn id='has-pseudo'>:has()</dfn>,
-	is a functional pseudo-class taking a <<relative-selector-list>> as an argument.
+	is a functional pseudo-class taking a <<relative-real-selector-list>> as an argument.
 	It represents an element if any of the <a>relative selectors</a>
 	would match at least one element
 	when [=anchor element|anchored against=] this element.
@@ -2905,7 +2905,7 @@ Child-indexed Pseudo-classes</h3>
 	are among <var>An+B</var>th elements
 	from the list composed of
 	their <a>inclusive siblings</a> that match the <a>selector list</a> <var>S</var>,
-	which is a <<complex-selector-list>>.
+	which is a <<complex-real-selector-list>>.
 	If <var>S</var> is omitted,
 	it defaults to ''*|*''.
 
@@ -3002,7 +3002,7 @@ Child-indexed Pseudo-classes</h3>
 	from the list composed of
 	their <a>inclusive siblings</a> that match the <a>selector list</a> <var>S</var>,
 	counting backwards from the end.
-	<var>S</var> is <<complex-selector-list>>.
+	<var>S</var> is <<complex-real-selector-list>>.
 	If <var>S</var> is omitted,
 	it defaults to ''*|*''.
 
@@ -3530,17 +3530,25 @@ Grammar</h2>
 
 	<dfn>&lt;complex-selector-list></dfn> = <<complex-selector>>#
 
+	<dfn>&lt;complex-real-selector-list></dfn> = <<complex-real-selector>>#
+
 	<dfn>&lt;compound-selector-list></dfn> = <<compound-selector>>#
 
 	<dfn>&lt;simple-selector-list></dfn> = <<simple-selector>>#
 
 	<dfn>&lt;relative-selector-list></dfn> = <<relative-selector>>#
 
+	<dfn>&lt;relative-real-selector-list></dfn> = <<relative-real-selector>>#
+
 	<dfn>&lt;complex-selector></dfn> = [ <<compound-selector>>? <<pseudo-compound-selector>>* ]!
 	     [ <<combinator>>? [ <<compound-selector>>? <<pseudo-compound-selector>>* ]!  ]*
 
+	<dfn>&lt;complex-real-selector></dfn> = <<compound-selector>> [ <<combinator>>? <<compound-selector>> ]*
+
 	<dfn>&lt;relative-selector></dfn> = <<combinator>>? <<complex-selector>>
 
+	<dfn>&lt;relative-real-selector></dfn> = <<combinator>>? <<complex-real-selector>>
+
 	<dfn>&lt;compound-selector></dfn> = [ <<type-selector>>? <<subclass-selector>>* ]!
 
 	<dfn>&lt;pseudo-compound-selector></dfn> =  <<pseudo-element-selector>> <<pseudo-class-selector>>*