anchor.diff:      [<Import>]
       member val TagAggregatorFactoryService: IViewTagAggregatorFactoryService = null with get, set
       interface IWpfTextViewMarginProvider with
  -        member x.CreateMargin(wpfTextViewHost: IWpfTextViewHost, _marginContainer: IWpfTextViewMargin): IWpfTextViewMargin = 
  +        member x.CreateMargin(wpfTextViewHost: IWpfTextViewHost, marginContainer: IWpfTextViewMargin): IWpfTextViewMargin = 
               let textView = wpfTextViewHost.TextView
  -            new UnusedDeclarationMargin(textView, x.TagAggregatorFactoryService.CreateTagAggregator<UnusedDeclarationTag>(textView)) :> _
  +            new UnusedDeclarationMargin(textView, marginContainer,
  +                    x.TagAggregatorFactoryService.CreateTagAggregator<UnusedDeclarationTag>(textView)) :> _
           
           
   
  
positive.code: open Microsoft.VisualStudio.Text.Tagging
  
  [<Name("UnusedDeclarationMargin")>]
  type UnusedDeclarationMargin(textView: IWpfTextView, tagAggregator: ITagAggregator<UnusedDeclarationTag>) =
      inherit Canvas()
  
      let children = base.Children
  
      let updateDisplay () =
           if not textView.IsClosed then
              children.Clear()
              let span = SnapshotSpan(textView.TextBuffer.CurrentSnapshot, 0, textView.TextBuffer.CurrentSnapshot.Length)
              tagAggregator.GetTags(span)
              |> Seq.map (fun span -> 
  
negative.code:                 textView.TextSnapshot.GetLineNumberFromPosition(pos))
              |> Seq.distinct
              |> Seq.iter (fun lineNo ->                
                      let markerHeight = min 4.0 (lineHeight / 2.0)
                      let markerWidth = verticalScrollBar.MarginSize
                      let marker = Rectangle(Fill = Brushes.Orange, StrokeThickness = 2.0, Stroke = Brushes.DarkOrange,
                                             Height = markerHeight, Width = markerWidth)
                      Canvas.SetLeft(marker, -markerWidth)
                      Canvas.SetTop(marker, float lineNo * lineHeight)
                      marker.MouseDown.Add(fun _ -> 
                          let line = textView.TextSnapshot.GetLineFromLineNumber(lineNo)
                          textView.ViewScroller.EnsureSpanVisible(SnapshotSpan(line.Start, 0), EnsureSpanVisibleOptions.AlwaysCenter))
  