All: inline jQuery.isWindow as it'll be removed in jQuery 4.0

Author: mgol

ui/position.js

@@ -48,6 +48,10 @@ function parseCss( element, property ) {
 	return parseInt( $.css( element, property ), 10 ) || 0;
 }
 
+function isWindow( obj ) {
+	return obj != null && obj === obj.window;
+}
+
 function getDimensions( elem ) {
 	var raw = elem[ 0 ];
 	if ( raw.nodeType === 9 ) {
@@ -57,7 +61,7 @@ function getDimensions( elem ) {
 			offset: { top: 0, left: 0 }
 		};
 	}
-	if ( $.isWindow( raw ) ) {
+	if ( isWindow( raw ) ) {
 		return {
 			width: elem.width(),
 			height: elem.height(),
@@ -119,12 +123,12 @@ $.position = {
 	},
 	getWithinInfo: function( element ) {
 		var withinElement = $( element || window ),
-			isWindow = $.isWindow( withinElement[ 0 ] ),
+			isElemWindow = isWindow( withinElement[ 0 ] ),
 			isDocument = !!withinElement[ 0 ] && withinElement[ 0 ].nodeType === 9,
-			hasOffset = !isWindow && !isDocument;
+			hasOffset = !isElemWindow && !isDocument;
 		return {
 			element: withinElement,
-			isWindow: isWindow,
+			isWindow: isElemWindow,
 			isDocument: isDocument,
 			offset: hasOffset ? $( element ).offset() : { left: 0, top: 0 },
 			scrollLeft: withinElement.scrollLeft(),