MaterialWindow - Fixing dnd issue. We must need to attach the widget first before initializing the dnd area.

Author: kevzlou7979

src/test/java/gwt/material/design/addins/client/ui/MaterialWindowTest.java

@@ -114,20 +114,19 @@ public void testClearContent() {
 
     //TODO: Failed Tests
     public void testDndArea() {
-        /*// UiBinder
+        // UiBinder
         // given
-        MaterialWindow window = getWidget(false);
+        MaterialWindow window = getWidget(true);
+
         MaterialPanel dndArea = new MaterialPanel();
         window.setDndArea(dndArea);
 
-        attachWidget();
-
         window.open();
 
         assertTrue(window.getDnd().getDragOptions().restrict.restriction instanceof Element);
         Element element = (Element) window.getDnd().getDragOptions().restrict.restriction;
         assertEquals(dndArea.getElement().getInnerHTML(), element.getInnerHTML());
-        assertEquals(dndArea.getElement(), element);*/
+        assertEquals(dndArea.getElement(), element);
     }
 
     @Override