Fix node repainting

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Drawing/Views/MaterialNodeView.cs

                     m_PreviewContainer.Add(m_PreviewImage);
                 m_PreviewImage.image = preview.texture;
             }
-//            Dirty(ChangeType.Layout);
+            Dirty(ChangeType.Repaint);
         }
 
         void UpdateControls(MaterialNodePresenter nodeData)
 
             m_ControlsContainer.Clear();
             m_CurrentControls.Clear();
+            Dirty(ChangeType.Layout);
 
             if (!nodeData.expanded)
                 return;