Make test for EditorSaveEvent.bean field

* Fixes #8810, #8658

server/src/main/java/com/vaadin/ui/components/grid/EditorImpl.java

     }
 
     private void doCancel(boolean afterBeingSaved) {
+        T editedBean = edited;
         doClose();
         if (!afterBeingSaved) {
-            eventRouter.fireEvent(new EditorCancelEvent<>(this, edited));
+            eventRouter.fireEvent(new EditorCancelEvent<>(this, editedBean));
         }
     }
 

server/src/test/java/com/vaadin/tests/server/component/grid/EditorImplTest.java

 import java.util.Optional;
 import java.util.stream.Stream;
 
+import com.vaadin.ui.Grid;
 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
     public static class TestEditorImpl extends EditorImpl<Object> implements
             EditorSaveListener<Object>, EditorCancelListener<Object> {
 
+        @Override
+        public void doEdit(Object bean) {
+            super.doEdit(bean);
+        }
+
         public TestEditorImpl() {
             super(new PropertySet<Object>() {
                 @Override
                     return null;
                 }
             });
+
+        }
+
+        @Override
+        public Grid<Object> getParent() {
+            return new Grid<>();
         }
 
         EditorCancelEvent<Object> cancelEvent;
 
         EditorServerRpc rpc;
 
-        @Override
-        public boolean isOpen() {
-            return true;
-        }
-
         @Override
         public boolean isBuffered() {
             return true;
         }
     }
 
+    private Object beanToEdit = new Object();
+
     private TestEditorImpl editor;
     private Binder<Object> binder;
 
         editor.addCancelListener(editor);
         binder = Mockito.mock(Binder.class);
         editor.setBinder(binder);
+        editor.setEnabled(true);
+        editor.doEdit(beanToEdit);
     }
 
     @Test
         Assert.assertNull(editor.cancelEvent);
 
         Assert.assertEquals(editor, editor.saveEvent.getSource());
+        Assert.assertEquals(beanToEdit, editor.saveEvent.getBean());
     }
 
     @Test
         Assert.assertNotNull(editor.cancelEvent);
 
         Assert.assertEquals(editor, editor.cancelEvent.getSource());
+
+        Assert.assertEquals(beanToEdit, editor.cancelEvent.getBean());
     }
 
     @Test
         Assert.assertNull(editor.cancelEvent);
 
         Assert.assertEquals(editor, editor.saveEvent.getSource());
+
+        Assert.assertEquals(beanToEdit, editor.saveEvent.getBean());
     }
 
     @Test
         Assert.assertNotNull(editor.cancelEvent);
 
         Assert.assertEquals(editor, editor.cancelEvent.getSource());
+
+        Assert.assertEquals(beanToEdit, editor.cancelEvent.getBean());
     }
 
     @Test