title: Divider in a NavigationView (in BottomSheetDialogFragment) doesn't shown?
body: <p>I have a NavigationView in BottomSheetDialogFragment. But divider between groups menu doesn't appear.
  I checked some solutions, for example here <a href="https://stackoverflow.com/questions/30625280/how-to-create-a-simple-divider-in-the-new-navigationview">How to create a simple divider in the new NavigationView?</a>
  But it not works for me.</p>
  
  <p>nav_menu.xml</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;menu xmlns:android="http://schemas.android.com/apk/res/android"&gt;
      &lt;item
          android:id="@+id/item1"
          android:title="Item 1" /&gt;
      &lt;item
          android:id="@+id/item2"
          android:title="Item 2" /&gt;
  
      &lt;group
          android:id="@+id/group1"
          android:checkableBehavior="single"&gt;
          &lt;item
              android:id="@+id/g_item1"
              android:title="Group Item 1" /&gt;
          &lt;item
              android:id="@+id/g_item2"
              android:title="Group Item 2" /&gt;
      &lt;/group&gt;
  
      &lt;group
          android:id="@+id/group2"
          android:checkableBehavior="single"&gt;
          &lt;item
              android:id="@+id/g2_item1"
              android:title="Group Item 1" /&gt;
          &lt;item
              android:id="@+id/g2_item2"
              android:title="Group Item 2" /&gt;
      &lt;/group&gt;
  
      &lt;item android:id="@+id/submenu"
          android:title="Sub menu" &gt;
          &lt;menu&gt;
              &lt;item
                  android:id="@+id/sub_item1"
                  android:title="Sub Item 1" /&gt;
              &lt;item
                  android:id="@+id/sub_item2"
                  android:title="Sub Item 2" /&gt;
          &lt;/menu&gt;
      &lt;/item&gt;
  &lt;/menu&gt;
  </code></pre>
  
  <p>fragment_bottom_sheet.xml</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/apk/res-auto"
      xmlns:tools="http://schemas.android.com/tools"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:orientation="vertical"
      tools:context=".BottomSheetFragment"&gt;
  
      &lt;com.google.android.material.navigation.NavigationView
          android:id="@+id/dialogFragment"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          app:menu="@menu/nav_menu" /&gt;
  &lt;/FrameLayout&gt;
  </code></pre>
  
  <p>and BottomSheetDialogFragment</p>
  
  <pre><code>public class BottomSheetFragment extends BottomSheetDialogFragment {
  
      View view;
      public BottomSheetFragment() {
          // Required empty public constructor
      }
  
      @Override
      public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
          view = inflater.inflate(R.layout.fragment_bottom_sheet, container, false);
          NavigationView navigationView = view.findViewById(R.id.dialogFragment);
          navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
              @Override
              public boolean onNavigationItemSelected(@NonNull MenuItem menuItem) {
                  NavController navController = Navigation.findNavController(getActivity(), R.id.navGraph);
                  dismiss();
                  return NavigationUI.onNavDestinationSelected(menuItem, navController);
              }
          });
          return view;
      }
  }
  </code></pre>
  
  <p>Result is here</p>
  
  <p><a href="https://i.stack.imgur.com/XjSfi.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/XjSfi.jpg" alt="enter image description here"></a></p>
  
  <p>I need this result</p>
  
  <p><a href="https://i.stack.imgur.com/lrm5X.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/lrm5X.jpg" alt="enter image description here"></a></p>
  
  <p>Edited:
  See result from Android Studio and from AVD</p>
  
  <p><a href="https://i.stack.imgur.com/3pUBP.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/3pUBP.jpg" alt="enter image description here"></a></p>