avm2: Implement XML.contains

[cy-polo]

XML.contains() method implemented.

Test:

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" minWidth="955" minHeight="600" creationComplete="init()">
	<mx:Script>
		<![CDATA[			
			private function init():void {
				var xml:XML = 
					<order>
						<item>Rice</item>
						<item>Kung Pao Shrimp</item>
					</order>;
				trace(xml.item[0].contains(<item>Rice</item>)); // true
				trace(xml.item[1].contains(<item>Kung Pao Shrimp</item>)); // true
				trace(xml.item[1].contains(<item>MSG</item>)); // false
			}
		]]>
	</mx:Script>
</mx:Application>

[sleepycatcoding]

Thank you and welcome! 👋

[sleepycatcoding]

Just a few last nits, otherwise LGTM.

[torokati44]

Can I ask for the commit history to be cleaned up a bit before merging? 😊

[sleepycatcoding]

Can I ask for the commit history to be cleaned up a bit before merging? 😊

I had the plan to squash it 😄