[material-ui][Drawer] Fix issue with main window being used instead o…

…f iframe's window (#43818)

packages/mui-utils/src/getScrollbarSize/getScrollbarSize.ts

@@ -3,5 +3,5 @@
 export default function getScrollbarSize(doc: Document): number {
   // https://developer.mozilla.org/en-US/docs/Web/API/Window/innerWidth#usage_notes
   const documentWidth = doc.documentElement.clientWidth;
-  return Math.abs(window.innerWidth - documentWidth);
+  return Math.abs(doc.defaultView!.innerWidth - documentWidth);
 }