Fix #7472 and added test for #3113

- Forms with an input that has either name="action" or name="some-other-attr-on-the-form" caused problems in IE6/7.  This is fixed.

- Changed check in $.attr for ret === null to typeof ret === "object" to catch any inputs that are accidentally retrieved in IE6/7, since attributes cannot be set to objects and typeof null === "object"

src/attributes.js

@@ -320,7 +320,8 @@ jQuery.extend({
 				ret = elem.getAttribute( name );
 
 				// Non-existent attributes return null, we normalize to undefined
-				return ret === null || ret === "null" ?
+				// Instead of checking for null, we check for typeof object to catch inputs in IE6/7. Bug #7472
+				return typeof ret === "object" || ret === "null" ?
 					undefined :
 					ret;
 			}

test/index.html

@@ -203,6 +203,7 @@ <h2 id="qunit-userAgent"></h2>
 			<select name="D4" disabled="disabled">
 				<option selected="selected" value="NO">NO</option>
 			</select>
+			<input name="id">
 		</form>
 		<div id="moretests">
 			<form>

test/unit/attributes.js

@@ -69,7 +69,7 @@ test("prop(String, Object)", function() {
 });
 
 test("attr(String)", function() {
-	expect(20);
+	expect(22);
 
 	equals( jQuery('#text1').attr('type'), "text", 'Check for type attribute' );
 	equals( jQuery('#radio1').attr('type'), "radio", 'Check for type attribute' );
@@ -82,8 +82,10 @@ test("attr(String)", function() {
 	equals( jQuery('#name').attr('name'), "name", 'Check for name attribute' );
 	equals( jQuery('#text1').attr('name'), "action", 'Check for name attribute' );
 	ok( jQuery('#form').attr('action').indexOf("formaction") >= 0, 'Check for action attribute' );
-	// Temporarily disabled. See: #4299
-	// ok( jQuery('#form').attr('action','newformaction').attr('action').indexOf("newformaction") >= 0, 'Check that action attribute was changed' );
+	// [7472] & [3113] (form contains an input with name="action" or name="id")
+	equals( jQuery('#form').attr('action','newformaction').attr('action'), 'newformaction', 'Check that action attribute was changed' );
+	equals( jQuery('#testForm').removeAttr('id').attr('id'), undefined, 'Test that id does not equal the input with name=id after id is removed [#7472]' );
+
 	equals( jQuery('#text1').attr('maxlength'), '30', 'Check for maxlength attribute' );
 	equals( jQuery('#text1').attr('maxLength'), '30', 'Check for maxLength attribute' );
 	equals( jQuery('#area1').attr('maxLength'), '30', 'Check for maxLength attribute' );