0000581: crash when editing duplicated sketch

git-svn-id: https://free-cad.svn.sourceforge.net/svnroot/free-cad/trunk@5427 e8eeb9e2-ec13-0410-a4a9-efa5cf37419d

src/App/Document.cpp

@@ -1529,6 +1529,7 @@ DocumentObject* Document::_copyObject(DocumentObject* obj, std::map<DocumentObje
     }
 
      // unmark to be not re-computed later
+    copy->onFinishDuplicating();
     copy->purgeTouched();
     return copy;
 }

src/App/DocumentObject.h

@@ -181,6 +181,8 @@ protected:
     virtual void onChanged(const Property* prop);
     /// get called after a document has been fully restored
     virtual void onDocumentRestored() {}
+    /// get called after duplicating an object
+    virtual void onFinishDuplicating() {}
 
      /// python object of this class and all descendend
 protected: // attributes