[cssom] Define serialization of >> and || combinators

Author: Simon Pieters

cssom/Overview.bs

@@ -550,10 +550,11 @@ part of the chain of the selector, and finally return
  <li>If this is not the last part of the chain of the selector append a
  single SPACE (U+0020), followed by the combinator
  "<code lt>></code>",
- "<code lt>+</code>", or
- "<code lt>~</code>"
+ "<code lt>+</code>",
+ "<code lt>~</code>",
+ "<code lt>||</code>",
  as appropriate, followed by another single SPACE (U+0020) if the combinator was
- not whitespace, to <var>s</var>.
+ not a <a>descendant combinator</a> (whitespace or "<code lt>>></code>"), to <var>s</var>.
 
  <li>If this is the last part of the chain of the selector and there is
  a pseudo-element, append "<code lt>::</code>" followed by the name of the
@@ -2998,6 +2999,13 @@ The {{PseudoElement}} Interface {#the-pseudoelement-interface}
 <code data-anolis-spec=dom>Element</code> object.
 
 <pre class=idl>interface PseudoElement {
+<!-- XXX
+  // type
+  // style
+  // ownerElement
+  // querySelector should return PseudoElements
+  // Extend Event to expose PseudoElement?
+-->
 };
 
 PseudoElement implements GetStyleUtils;</pre>
@@ -3191,7 +3199,6 @@ Acknowledgments {#acknowledgments}
 ==================================
 
 The editors would like to thank
-
 Alexey Feldgendler,
 Bj&ouml;rn H&ouml;hrmann,
 Boris Zbasky,
@@ -3213,11 +3220,9 @@ Philip Taylor,
 Robert O'Callahan,
 Simon Sapin,
 Sjoerd Visscher,
-<!--Simon Pieters,-->
 Sylvain Galineau,
 Tarquin Wilton-Jones, and
 Zack Weinberg
-
 for contributing to this specification.
 
 Additional thanks to Ian Hickson for writing the