document CSSStyleSheet support in DOM shim

Author: thescientist13

docs/pages/index.md

@@ -20,6 +20,7 @@ $ npm install wc-compiler --save-dev
     - `[get|set|has]Attribute`
 1. `<template>` / `DocumentFragment`
 1. `addEventListener` (as a no-op)
+1. Supports `CSSStyleSheet` (all methods act as no-ops)
 1. Recursive rendering of nested custom elements
 1. Metadata and runtime hints to support various progressive hydration and lazy loading strategies
 

src/dom-shim.js

@@ -2,7 +2,8 @@ function noop() { }
 
 // https://developer.mozilla.org/en-US/docs/Web/API/CSSStyleSheet/CSSStyleSheet
 class CSSStyleSheet {
-  constructor() { }
+  insertRule() { }
+  deleteRule() { }
   replace() { }
   replaceSync() { }
 }