[leap5 -> main] in undo tests, create undo_index in CB memory segment and remove removed_nodes_tracker

include/chainbase/undo_index.hpp

@@ -404,41 +404,6 @@ namespace chainbase {
             BOOST_THROW_EXCEPTION( std::logic_error{ "could not modify object, most likely a uniqueness constraint was violated" } );
       }
 
-      // Allows testing whether a value has been removed from the undo_index.
-      //
-      // The lifetime of an object removed through a removed_nodes_tracker
-      // does not end before the removed_nodes_tracker is destroyed or invalidated.
-      //
-      // A removed_nodes_tracker is invalidated by the following members of undo_index:
-      // start_undo_session, commit, squash, and undo.
-      class removed_nodes_tracker {
-       public:
-         explicit removed_nodes_tracker(undo_index& idx) : _self(&idx) {}
-         ~removed_nodes_tracker() {
-            _removed_values.clear_and_dispose([this](value_type* obj) { _self->dispose_node(*obj); });
-         }
-         removed_nodes_tracker(const removed_nodes_tracker&) = delete;
-         removed_nodes_tracker& operator=(const removed_nodes_tracker&) = delete;
-         bool is_removed(const value_type& obj) const {
-            return undo_index::get_removed_field(obj) == erased_flag;
-         }
-         // Must be used in place of undo_index::remove
-         void remove(const value_type& obj) {
-            _self->remove(obj, *this);
-         }
-       private:
-         friend class undo_index;
-         void save(value_type& obj) {
-            undo_index::set_removed_field(obj, erased_flag);
-            _removed_values.push_front(obj);
-         }
-         undo_index* _self;
-         list_base<node, index0_type> _removed_values;
-      };
-      auto track_removed() {
-         return removed_nodes_tracker(*this);
-      }
-
       void remove( const value_type& obj ) noexcept {
          auto& node_ref = const_cast<value_type&>(obj);
          erase_impl(node_ref);
@@ -447,16 +412,6 @@ namespace chainbase {
          }
       }
 
-    private:
-
-      void remove( const value_type& obj, removed_nodes_tracker& tracker ) noexcept {
-         auto& node_ref = const_cast<value_type&>(obj);
-         erase_impl(node_ref);
-         if(on_remove(node_ref)) {
-            tracker.save(node_ref);
-         }
-      }
-
     public:
 
       template<typename CompatibleKey>