remove function pointer initialization

... to have a std::bad_function_call exception in case of an uninitialized function pointer

GUI/Models/SelectionDescriptor.h

@@ -40,25 +40,14 @@ using std::function;
 //! member, a std::variant or any other construction to define a selection.
 template <typename T> class SelectionDescriptor {
 public:
-    SelectionDescriptor()
-    {
-        // initialize function pointers to a lambda which throws an error. This helps later on if
-        // accidentally the real initialization has been forgotten.
-        setCurrentIndex = [](int) { throw std::runtime_error("Function pointer not initialized"); };
-
-        currentIndex = []() -> int {
-            throw std::runtime_error("Function pointer not initialized");
-        };
-
-        currentItem = []() -> T { throw std::runtime_error("Function pointer not initialized"); };
-    }
+    SelectionDescriptor() = default;
 
     //! Initialize the members by means of a GroupItem.
     //!
     //! currentItem can only be initialized if the template parameter is a pointer (like
     //! RotationItem*). If it is e.g. a std::variant<>, the currentItem has to be initialized by the
     //! caller. Only for easier migration. Should be removed after SessionItem refactoring.
-    explicit SelectionDescriptor(GroupItem* item) : SelectionDescriptor()
+    explicit SelectionDescriptor(GroupItem* item)
     {
         label = item->displayName();
         options = item->value().value<ComboProperty>().getValues();