Update and rename detect-disabled.js to detect.js

polyfills/Event/focusin/detect.js

@@ -0,0 +1,32 @@
+/*
+ * The detect and tests for the focusin/focusout polyfill have been shown to not work reliably. 
+ * See https://github.com/Financial-Times/polyfill-service/issues/213 for details.
+ * The polyfill itself appears to work fine, but events programmatically fired during page load 
+ * while dev tools is open appear not to be observable by the polyfill, which makes the test and 
+ * detect unreliable.  We're continuing to serve the polyfill as it's pretty simple but would 
+ * love to get some better insight into this problem.
+ */
+
+(function(support, html, a) {
+	if ('onfocusin' in window) {
+		return true;
+	}
+
+	function onfocusin() {
+		support = true;
+	}
+
+	a.href = '#';
+
+	if ('addEventListener' in a) {
+		a.addEventListener('focusin', onfocusin);
+	} else {
+		a.attachEvent('onfocusin', onfocusin);
+	}
+
+	html.appendChild(a).focus();
+
+	html.removeChild(a);
+
+	return support;
+}(false, document.documentElement, document.createElement('a')));