Fix typo in a comment

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78268 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/propgrid/propgrid.cpp

@@ -1852,7 +1852,7 @@ void wxPropertyGrid::OnPaint( wxPaintEvent& WXUNUSED(event) )
     }
     wxASSERT( dcPtr );
     PrepareDC(*dcPtr);
-    // Unused area will be cleared when drawing then items
+    // Unused area will be cleared when drawing the items
 /*
     dcPtr->SetBackground(m_colEmptySpace);
     dcPtr->Clear();