Set the input type for firefox. Fix a support test.

src/manipulation/support.js

@@ -7,6 +7,8 @@ define([
 		div = document.createElement("div"),
 		input = document.createElement("input");
 
+	input.type = "checkbox";
+
 	// Setup
 	div.setAttribute( "className", "t" );
 	div.innerHTML = "  <link/><table></table><a href='/a'>a</a>";

src/support.js

@@ -16,6 +16,8 @@ for ( i in jQuery( support ) ) {
 support.ownLast = i !== "0";
 
 // Note: most support tests are defined in their respective modules.
+// false until the test is run
+support.inlineBlockNeedsLayout = false;
 
 jQuery(function() {
 	// We need to execute this one support test ASAP because we need to know
@@ -42,9 +44,6 @@ jQuery(function() {
 
 	body.appendChild( container ).appendChild( div );
 
-	// Will be changed later if needed.
-	support.inlineBlockNeedsLayout = false;
-
 	if ( typeof div.style.zoom !== strundefined ) {
 		// Support: IE<8
 		// Check if natively block-level elements act like inline-block
@@ -52,9 +51,8 @@ jQuery(function() {
 		// them layout
 		div.innerHTML = "";
 		div.style.cssText = divReset + "width:1px;padding:1px;display:inline;zoom:1";
-		support.inlineBlockNeedsLayout = ( div.offsetWidth === 3 );
 
-		if ( support.inlineBlockNeedsLayout ) {
+		if ( (support.inlineBlockNeedsLayout = div.offsetWidth === 3) ) {
 			// Prevent IE 6 from affecting layout for positioned elements #11048
 			// Prevent IE from shrinking the body in IE 7 mode #12869
 			// Support: IE<8

test/unit/support.js

 module("support", { teardown: moduleTeardown });
 
-var computedSupport = getComputedSupport( jQuery.support );
-
 function getComputedSupport( support ) {
 	var prop,
 		result = {};
@@ -17,6 +15,8 @@ function getComputedSupport( support ) {
 	return result;
 }
 
+var computedSupport = getComputedSupport( jQuery.support );
+
 test( "zoom of doom (#13089)", function() {
 	expect( 1 );