Add readyWait tests. Fixes #8145.

Adds tests for the fix to #6781.

test/data/readywaitasset.js

+var delayedMessage = "It worked!";

test/data/readywaitloader.js

+// Simple script loader that uses jQuery.readyWait
+
+//Hold on jQuery!
+jQuery.readyWait++;
+
+var readyRegExp = /^(complete|loaded)$/;
+
+function assetLoaded( evt ){
+	var node = evt.currentTarget || evt.srcElement;
+	if ( evt.type === "load" || readyRegExp.test(node.readyState) ) {
+		jQuery.ready(true);
+	}
+}
+
+setTimeout( function() {
+	var script = document.createElement("script");
+	script.type = "text/javascript";
+	if ( script.addEventListener ) {
+		script.addEventListener( "load", assetLoaded, false );
+	} else {
+		script.attachEvent( "onreadystatechange", assetLoaded );
+	}
+	script.src = "data/readywaitasset.js";
+	document.getElementsByTagName("head")[0].appendChild(script);
+}, 2000 );

test/readywait.html

+<!DOCTYPE html>
+<html>
+<!--
+	Test for jQuery.readyWait. Needs to be a
+	standalone test since it deals with DOM
+	ready.
+-->
+<head>
+	<title>
+		jQuery.readyWait Test
+	</title>
+	<style>
+		div { margin-top: 10px; }
+		#output { background-color: green }
+		#expectedOutput { background-color: green }
+	</style>
+	<script src="../src/core.js"></script>
+	<script src="../src/support.js"></script>
+	<script src="../src/data.js"></script>
+	<script src="../src/queue.js"></script>
+	<script src="../src/attributes.js"></script>
+	<script src="../src/event.js"></script>
+	<script src="../src/sizzle/sizzle.js"></script>
+	<script src="../src/sizzle-jquery.js"></script>
+	<script src="../src/traversing.js"></script>
+	<script src="../src/manipulation.js"></script>
+	<script src="../src/css.js"></script>
+	<script src="../src/ajax.js"></script>
+	<script src="../src/ajax/jsonp.js"></script>
+	<script src="../src/ajax/script.js"></script>
+	<script src="../src/ajax/xhr.js"></script>
+	<script src="../src/effects.js"></script>
+	<script src="../src/offset.js"></script>
+	<script src="../src/dimensions.js"></script>
+
+	<!-- Load the script loader that uses
+		jQuery.readyWait -->
+	<script src="data/readywaitloader.js"></script>
+
+	<script type="text/javascript">
+	jQuery(function() {
+		// The delayedMessage is defined by
+		// the readywaitasset.js file, so the
+		// next line will only work if this DOM
+		// ready callback is called after readyWait
+		// has been decremented by readywaitloader.js
+		// If an error occurs.
+		jQuery("#output").append(delayedMessage);
+	});
+	</script>
+</head>
+<body>
+	<h1>
+		jQuery.readyWait Test
+	</h1>
+	<p>
+		This is a test page for jQuery.readyWait, that was
+		added due to this ticket
+		<a href="http://bugs.jquery.com/ticket/6781">#6781</a>.
+	</p>
+	<p>
+	Test for jQuery.readyWait, which can be used
+	by plugins and other scripts to indicate something
+	important to the page is still loading and needs
+	to block the DOM ready callbacks that are registered
+	with jQuery.
+	</p>
+	<p>
+	Script loaders are the most likely kind of script
+	to use jQuery.readyWait, but it could be used by
+	other things like a script that loads a CSS file
+	and wants to pause the DOM ready callbacks.
+	</p>
+	<p>
+	<strong>Expected Result</strong>: The text
+	<span id="expectedOutput">It Worked!</span>
+	appears below after about <strong>2 seconds.</strong>
+	</p>
+	<p>
+	If there is an error in the console,
+	or the text does not show up, then the test failed.
+	</p>
+	<div id="output"></div>
+</body>
+</html>