Landing pull request 562. Make sure runtimeStyle isn't affected by dimensions. Fixes #9233.

More Details:
 - https://github.com/jquery/jquery/pull/562
 - http://bugs.jquery.com/ticket/9233

src/css.js

@@ -285,9 +285,8 @@ if ( document.defaultView && document.defaultView.getComputedStyle ) {
 
 if ( document.documentElement.currentStyle ) {
 	currentStyle = function( elem, name ) {
-		var left,
+		var left, rsLeft,
 			ret = elem.currentStyle && elem.currentStyle[ name ],
-			rsLeft = elem.runtimeStyle && elem.runtimeStyle[ name ],
 			style = elem.style;
 
 		if ( ret === null && style ) {
@@ -300,8 +299,10 @@ if ( document.documentElement.currentStyle ) {
 		// If we're not dealing with a regular pixel number
 		// but a number that has a weird ending, we need to convert it to pixels
 		if ( !rnumpx.test( ret ) && rnum.test( ret ) ) {
+
 			// Remember the original values
 			left = style.left;
+			rsLeft = elem.runtimeStyle && elem.runtimeStyle.left;
 
 			// Put in the new values to get a computed value out
 			if ( rsLeft ) {

test/unit/dimensions.js

@@ -245,6 +245,29 @@ test("child of a hidden elem has accurate inner/outer/Width()/Height()  see #944
 	$divNormal.remove();
 });
 
+test("getting dimensions shouldnt modify runtimeStyle see #9233", function() {
+	expect( 1 );
+
+	var $div = jQuery( "<div>" ).appendTo( "#qunit-fixture" ),
+		div = $div.get( 0 ),
+		runtimeStyle = div.runtimeStyle;
+
+	if ( runtimeStyle ) {
+		div.runtimeStyle.marginLeft = "12em";
+		div.runtimeStyle.left = "11em";
+	}
+
+	$div.outerWidth( true );
+
+	if ( runtimeStyle ) {
+		equal( div.runtimeStyle.left, "11em", "getting dimensions modifies runtimeStyle, see #9233" );
+	} else {
+		ok( true, "this browser doesnt support runtimeStyle, see #9233" );
+	}
+
+	$div.remove();
+});
+
 test("outerHeight()", function() {
 	expect(11);