presets options when empty

src/node_panel_brush.h

@@ -7,6 +7,7 @@
 #include "node_scroll.h"
 #include "node_text.h"
 #include "serializer.h"
+#include "node_button.h"
 
 class NodeButtonBrush : public NodeButtonCustom, public Serializer::Type
 {
@@ -82,6 +83,9 @@ class NodePanelBrushPreset : public Node
     NodeButtonCustom* m_btn_delete;
     NodeButtonCustom* m_btn_save;
     NodeButtonCustom* m_btn_menu;
+    NodeButton* m_btn_import;
+    NodeButton* m_btn_download;
+    Node* m_notification;
 public:
     Node* m_container;
     std::function<void(Node* target, std::shared_ptr<Brush>& brush)> on_brush_changed;