[material graph]Remove upgrade code, no needed yet.

MaterialGraphProject/Assets/UnityShaderEditor/Runtime/SubGraph/SubGraphNode.cs

         {
             get
             {
-
-                if (serializedVersion < kCurrentSerializedVersion)
-                    DoUpgrade();
-
                 if (string.IsNullOrEmpty(m_SerializedSubGraph))
                     return null;
 
                 OnEnable();
             }
         }
-
+        /*
+        if (serializedVersion<kCurrentSerializedVersion)
+                    DoUpgrade();
         [SerializeField]
         private string m_SubGraphAssetGuid;
 
             m_SerializedSubGraph = EditorJsonUtility.ToJson(helper, true);
             serializedVersion = kCurrentSerializedVersion;
             m_SubGraphAssetGuid = string.Empty;
-        }
+            mark dirty damn 
+        }*/
 #else
         public MaterialSubGraphAsset subGraphAsset {get; set:}
 #endif