Pending changes do not prevent route change

[Dergash]

Steps to reproduce:

1. Open default view( http://idocs.tesler.io/ui/#/screen/doc/view/list)
2. Scroll to the countries table and click a "Create" button
3. Click "Save" button without filling any field, "Name" field should be highlighted as required
4. Click "Example" menu item in the left screen menu

Expected behavior:
A popup with a warning that there are pending changes on the page with options to discard them or just close the popup, browser url is not changed

Actual behavior:
No popup, browser url is changed as if we navigated succesfully