App: [skip ci] fix Property::isSame() and subclasses by first comparing the pointers directly

src/App/PropertyLinks.cpp

@@ -86,6 +86,8 @@ void PropertyLinkBase::hasSetValue() {
 
 bool PropertyLinkBase::isSame(const Property &other) const
 {
+    if(&other == this)
+        return true;
     if(other.isDerivedFrom(PropertyLinkBase::getClassTypeId())
         || getScope() != static_cast<const PropertyLinkBase*>(&other)->getScope())
         return false;