Add help url placeholders for new pages

Bug: 38412798
Test: visual
Change-Id: I4ede523cb13790ea05309279f80a778b2086f850

src/com/android/settings/network/NetworkDashboardFragment.java

@@ -69,6 +69,11 @@ public class NetworkDashboardFragment extends DashboardFragment implements
         mNetworkResetController = new NetworkResetActionMenuController(context);
     }
 
+    @Override
+    protected int getHelpResource() {
+        return R.string.help_url_network_dashboard;
+    }
+
     @Override
     public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
         super.onCreateOptionsMenu(menu, inflater);