fix markdown example

dist/reveal.css

@@ -1,5 +1,5 @@
 /*!
-* reveal.js 4.0.0-dev (Sat Mar 07 2020)
+* reveal.js 4.0.0-dev (Mon Mar 09 2020)
 * https://revealjs.com
 * MIT licensed
 *

js/reveal.js

@@ -810,7 +810,7 @@ export default function( revealElement, options ) {
 
 		if( config.postMessage ) {
 			window.addEventListener( 'message', event => {
-				const data = event.data;
+				let data = event.data;
 
 				// Make sure we're dealing with JSON
 				if( typeof data === 'string' && data.charAt( 0 ) === '{' && data.charAt( data.length - 1 ) === '}' ) {

plugin/markdown/example.html

@@ -6,8 +6,8 @@
 
 		<title>reveal.js - Markdown Demo</title>
 
-		<link rel="stylesheet" href="../../css/reveal.css">
-		<link rel="stylesheet" href="../../css/theme/white.css" id="theme">
+		<link rel="stylesheet" href="../../dist/reveal.css">
+		<link rel="stylesheet" href="../../dist/theme/white.css" id="theme">
 
         <link rel="stylesheet" href="../../lib/css/monokai.css">
 	</head>
@@ -18,6 +18,17 @@
 
 			<div class="slides">
 
+                <section data-markdown>
+                    ```php
+                    public function foo()
+                    {
+                        $foo = array(
+                            'bar' => 'bar'
+                        )
+                    }
+                    ```
+                </section>
+
                 <!-- Use external markdown resource, separate slides by three newlines; vertical slides by two newlines -->
                 <section data-markdown="example.md" data-separator="^\n\n\n" data-separator-vertical="^\n\n"></section>
 
@@ -109,7 +120,7 @@
             </div>
 		</div>
 
-		<script src="../../js/reveal.js"></script>
+		<script src="../../dist/reveal.min.js"></script>
 
 		<script>