Don't swap to measure dimensions unless the element is display:none. #…

…807 Fixes #11293

src/css.js

@@ -480,7 +480,7 @@ jQuery.each([ "height", "width" ], function( i, name ) {
 	jQuery.cssHooks[ name ] = {
 		get: function( elem, computed, extra ) {
 			if ( computed ) {
-				if ( elem.offsetWidth !== 0 ) {
+				if ( elem.offsetWidth !== 0 || curCSS( elem, "display" ) !== "none" ) {
 					return getWidthOrHeight( elem, name, extra );
 				} else {
 					return jQuery.swap( elem, cssShow, function() {

test/unit/dimensions.js

@@ -299,6 +299,16 @@ test("outerWidth(true) returning % instead of px in Webkit, see #10639", functio
 	equal( el.outerWidth(true), 400, "outerWidth(true) and css('margin') returning % instead of px in Webkit, see #10639" );
 });
 
+test( "getting dimensions of zero width/height table elements shouldn't alter dimensions", function() {
+	expect( 1 );
+
+	var table = jQuery("<table><tbody><tr><td></td><td>a</td></tr><tr><td></td><td>a</td></tr></tbody></table>").appendTo("#qunit-fixture"),
+		elem = table.find("tr:eq(0) td:eq(0)");
+
+	table.find("td").css({ margin: 0, padding: 0 });
+	equal( elem.width(), elem.width(), "width() doesn't alter dimension values" );
+});
+
 test("box-sizing:border-box child of a hidden elem (or unconnected node) has accurate inner/outer/Width()/Height()  see #10413", function() {
 	expect(16);