rm default ctor and delayed init

GUI/Models/DoubleDescriptor.cpp

@@ -53,8 +53,6 @@ DoubleDescriptor::DoubleDescriptor(const QString& label, const QString& tooltip,
     path = [] { return QString(); };
 }
 
-DoubleDescriptor::DoubleDescriptor() {}
-
 DoubleDescriptor::DoubleDescriptor(const QString& label, const QString& tooltip, double* var,
                                    const variant<QString, Unit>& unit)
     : DoubleDescriptor(label, tooltip, 3, RealLimits::nonnegative(), var, unit)
@@ -70,11 +68,6 @@ DoubleDescriptor::DoubleDescriptor(const QString& label, const QString& tooltip,
 {
 }
 
-void DoubleDescriptor::init(SessionItem* item, const variant<QString, Unit>& unit)
-{
-    operator=(DoubleDescriptor(item, unit));
-}
-
 DoubleDescriptor::operator double() const
 {
     return get();

GUI/Models/DoubleDescriptor.h

@@ -67,14 +67,6 @@ private: // private as long as path initialization is not included in params (to
                      function<double()> getter, const variant<QString, Unit>& unit);
 
 public:
-    //! For delayed initialization.
-    //! Call init before usage!
-    DoubleDescriptor();
-
-    //! Initialize with a session item. To be used if an initialization already in the constructor
-    //! is not possible. Only for easier migration. Should be removed after SessionItem refactoring.
-    void init(SessionItem* item, const variant<QString, Unit>& unit);
-
     //! Return the current value of the handled parameter.
     operator double() const;