Make wxWindow::HasScrollbar() respect wxScrolled::ShowScrollbars().

Override CanScroll() in wxScrolled to return the real state of the scrollbar
instead of just relying on the wx[HV]SCROLL styles.

Closes #15440.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74714 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/scrlwing.cpp

@@ -1201,6 +1201,14 @@ wxScrollHelper::wxScrollHelper(wxWindow *winToScroll)
     m_yVisibility = wxSHOW_SB_DEFAULT;
 }
 
+bool wxScrollHelper::IsScrollbarShown(int orient) const
+{
+    wxScrollbarVisibility visibility = orient == wxHORIZONTAL ? m_xVisibility
+                                                              : m_yVisibility;
+
+    return visibility != wxSHOW_SB_NEVER;
+}
+
 void wxScrollHelper::DoShowScrollbars(wxScrollbarVisibility horz,
                                       wxScrollbarVisibility vert)
 {