Add help button support to wxRibbonBar.

Optionally show standard "Help" question mark button in the ribbon top right
corner and generate the appropriate event for it.

Closes #14576.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72495 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/ribbon/panel.cpp

@@ -1099,4 +1099,9 @@ wxRect wxRibbonPanel::GetExpandedPosition(wxRect panel,
     return best;
 }
 
+void wxRibbonPanel::HideIfExpanded()
+{
+    wxStaticCast(m_parent, wxRibbonPage)->HideIfExpanded();
+}
+
 #endif // wxUSE_RIBBON