Merge pull request Modernizr#640 from danielchatfield/master

Adds a test for the html5 'form' attribute.

feature-detects/forms-formattribute.js

@@ -0,0 +1,29 @@
+// Detects whether input form="form_id" is available on the platform
+// E.g. IE 10 (and below), don't support this
+Modernizr.addTest("formattribute", function() {
+	var form = document.createElement("form"),
+		input = document.createElement("input"),
+		div = document.createElement("div"),
+		id = "formtest"+(new Date().getTime()),
+		attr,
+		bool = false;
+
+		form.id = id;
+
+	//IE6/7 confuses the form idl attribute and the form content attribute
+	if(document.createAttribute){
+		attr = document.createAttribute("form");
+		attr.nodeValue = id;
+		input.setAttributeNode(attr);
+		div.appendChild(form);
+		div.appendChild(input);
+
+		document.documentElement.appendChild(div);
+
+		bool = form.elements.length === 1 && input.form == form;
+
+		div.parentNode.removeChild(div);
+	}
+
+	return bool;
+});