Small optimization

app/src/main/java/eu/faircode/email/ActivityView.java

@@ -874,7 +874,11 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
             public void onChanged(TupleOperationStats stats) {
                 navOperations.setWarning(stats != null && stats.errors != null && stats.errors > 0);
                 navOperations.setCount(stats == null ? 0 : stats.pending);
-                adapterNavMenu.notifyDataSetChanged();
+                int pos = adapterNavMenu.getPosition(navOperations);
+                if (pos < 0)
+                    adapterNavMenu.notifyDataSetChanged();
+                else
+                    adapterNavMenu.notifyItemChanged(pos);
             }
         });
 

app/src/main/java/eu/faircode/email/AdapterNavMenu.java

@@ -194,6 +194,10 @@ public class AdapterNavMenu extends RecyclerView.Adapter<AdapterNavMenu.ViewHold
         return items.get(pos);
     }
 
+    int getPosition(NavMenuItem item) {
+        return items.indexOf(item);
+    }
+
     private static class DiffCallback extends DiffUtil.Callback {
         private List<NavMenuItem> prev = new ArrayList<>();
         private List<NavMenuItem> next = new ArrayList<>();