nonvirtual reimplementation of CellularPanel::FindRect using nodes

src/TrackPanel.cpp

@@ -2088,20 +2088,6 @@ std::shared_ptr<TrackPanelNode> TrackPanel::Root()
    return std::make_shared< MainGroup >( *this );
 }
 
-wxRect TrackPanel::FindRect( const TrackPanelCell &cell )
-{
-   auto range = Cells();
-   auto end = range.second,
-      iter = std::find_if( range.first, end,
-         [&]( const decltype(*end) &pair )
-            { return pair.first.get() == &cell; }
-      );
-   if (iter == end)
-      return {};
-   else
-      return (*iter).second;
-}
-
 // This finds the rectangle of a given track (including all channels),
 // either that of the label 'adornment' or the track itself
 // The given track is assumed to be the first channel