Try to avoid a NullReferenceException:

Try to avoid a NullReferenceException:

Type:        System.NullReferenceException
Message:     Object reference not set to an instance of an object.
Source:      Cyberduck
Stack Trace: at Ch.Cyberduck.Ui.Controller.BrowserController.IsEditable(Path selected)
  at Ch.Cyberduck.Ui.Controller.BrowserController.UpdateEditIcon()
  at Ch.Cyberduck.Ui.Controller.BrowserController.View_BrowserSelectionChanged()
  at Ch.Cyberduck.Ui.Winforms.BrowserForm.browser_SelectionChanged(Object sender, EventArgs e)
  at BrightIdeasSoftware.ObjectListView.OnSelectionChanged(EventArgs e)
  at BrightIdeasSoftware.ObjectListView.HandleApplicationIdle(Object sender, EventArgs e)
  at BrightIdeasSoftware.TreeListView.HandleApplicationIdle(Object sender, EventArgs e)

git-svn-id: https://svn.cyberduck.io/trunk@17430 9e2dff1d-8f06-0410-b5b1-4d70b6340adc