AddedToLayout
bool AddedToLayout(BALMLayout* layout);
bool BALMLayout::_AddedTab(XTab* tab) { return tab->AddedToLayout(this); }
bool BALMLayout::_AddedTab(YTab* tab) { return tab->AddedToLayout(this); }
if (!tab->AddedToLayout(this)) {
if (!tab->AddedToLayout(this)) {
AddedToLayout(layout);
AddedToLayout(layout);