[core] don't scroll when closing a dialog

When a dialog gets closed, the previously
active element gets focus again. We don't
want the default scroll to top behavior.

Signed-off-by: Sven Efftinge <sven.efftinge@typefox.io>

packages/core/src/browser/dialogs.ts

@@ -243,7 +243,7 @@ export abstract class AbstractDialog<T> extends BaseWidget {
     close(): void {
         if (this.resolve) {
             if (this.activeElement) {
-                this.activeElement.focus();
+                this.activeElement.focus({ preventScroll: true });
             }
             this.resolve(undefined);
         }