Another PrepareForItem()-related fix in generic wxDataViewCtrl.

This fix is similar to the previous commit but more speculative, as we
currently don't have a bug scenario for it. Still, it seems to be wrong to
call PrepareForItem() just before GetLineStart() which undoes its effect, so
exchange the order of the calls.

See #16132.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76218 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/datavgen.cpp

@@ -2114,12 +2114,12 @@ void wxDataViewMainWindow::OnPaint( wxPaintEvent &WXUNUSED(event) )
                 dataitem = wxDataViewItem( wxUIntToPtr(item+1) );
             }
 
-            cell->PrepareForItem(model, dataitem, col->GetModelColumn());
-
             // update cell_rect
             cell_rect.y = GetLineStart( item );
             cell_rect.height = GetLineHeight( item );
 
+            cell->PrepareForItem(model, dataitem, col->GetModelColumn());
+
             // draw the background
             bool selected = m_selection.Index( item ) != wxNOT_FOUND;
             if ( !selected )