Fix SelectedItemIcon rendering on IE (#13731)

Change-Id: Ie6a3464399aba76b9299bcb7d326ef4e6b6c858b

client/src/com/vaadin/client/ui/VFilterSelect.java

@@ -1416,6 +1416,10 @@ public class VFilterSelect extends Composite implements Field, KeyDownHandler,
                 panel.remove(selectedItemIcon);
             }
             selectedItemIcon = new IconWidget(client.getIcon(iconUri));
+            // Older IE versions don't scale icon correctly if DOM
+            // contains height and width attributes.
+            selectedItemIcon.getElement().removeAttribute("height");
+            selectedItemIcon.getElement().removeAttribute("width");
             selectedItemIcon.addDomHandler(new LoadHandler() {
                 @Override
                 public void onLoad(LoadEvent event) {