improve scroll to line api.
improve scroll to line api.


AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit,AvaloniaUI/AvaloniaEdit