Hide 'Create new list' when sync is disabled

src/main/java/com/todoroo/astrid/adapter/FilterAdapter.java

@@ -235,7 +235,9 @@ public class FilterAdapter extends ArrayAdapter<FilterListItem> {
                     NavigationDrawerFragment.REQUEST_NEW_LIST));
         }
 
-        addSubMenu(R.string.gtasks_GPr_header, filterProvider.getGoogleTaskFilters(), true);
+        List<Filter> googleTaskFilters = filterProvider.getGoogleTaskFilters();
+        if (!googleTaskFilters.isEmpty()) {
+            addSubMenu(R.string.gtasks_GPr_header, googleTaskFilters, true);
 
             if (navigationDrawer) {
                 add(new NavigationDrawerAction(
@@ -244,6 +246,7 @@ public class FilterAdapter extends ArrayAdapter<FilterListItem> {
                         new Intent(activity, GoogleTaskListSettingsActivity.class),
                         NavigationDrawerFragment.REQUEST_NEW_GTASK_LIST));
             }
+        }
 
         if (navigationDrawer) {
             add(new NavigationDrawerSeparator());