Re-enabled intrusive_ptr

src/data/action/symbol_part.cpp

@@ -252,7 +252,7 @@ void CurveDragAction::move(const Vector2D& delta, double t) {
 
 ControlPointAddAction::ControlPointAddAction(const SymbolShapeP& shape, UInt insert_after, double t)
   : shape(shape)
-  , new_point(make_shared<ControlPoint>())
+  , new_point(make_intrusive<ControlPoint>())
   , insert_after(insert_after)
   , point1(shape->getPoint(insert_after))
   , point2(shape->getPoint(insert_after + 1))

src/data/card.hpp

@@ -25,7 +25,7 @@ DECLARE_POINTER_TYPE(StyleSheet);
 // ----------------------------------------------------------------------------- : Card
 
 /// A card from a card Set
-class Card : public IntrusivePtrVirtualBase {
+class Card : public IntrusivePtrVirtualBase, public IntrusiveFromThis<Card> {
   public:
   /// Default constructor, uses game_for_new_cards to make the game
   Card();