internal DependencyPropertyReferenceStep(IType declaringType, string memberName, IType valueType, DependencyPropertyImplementationBase implementation) : this(declaringType, memberName, valueType, implementation, PropertySortValue.NoValue)
 {
 }
 void Microsoft.Expression.DesignModel.Metadata.IPropertyImplementation.Invalidate()
 {
     this.implementation = UndefinedDependencyPropertyImplementation.Instance;
 }
 internal DependencyPropertyReferenceStep(IType declaringType, string memberName, IType valueType, DependencyPropertyImplementationBase implementation, int sortValue) : base(declaringType, memberName, valueType, sortValue)
 {
     this.implementation = implementation;
 }