[banshee] Fix crash caused if missing icons (BGO #607822)

[Gabriel Burt <gburt src gnome org>]

commit 45c0abe1e96a4c69df217e79e407f76ceb95c95e
Author: Gabriel Burt <gabriel burt gmail com>
Date:   Fri Jan 22 15:35:59 2010 -0800

    Fix crash caused if missing icons (BGO #607822)

 .../Banshee.Library.Gui/ImportDialog.cs            |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)
---
diff --git a/src/Core/Banshee.ThickClient/Banshee.Library.Gui/ImportDialog.cs b/src/Core/Banshee.ThickClient/Banshee.Library.Gui/ImportDialog.cs
index fd22d09..9287fff 100644
--- a/src/Core/Banshee.ThickClient/Banshee.Library.Gui/ImportDialog.cs
+++ b/src/Core/Banshee.ThickClient/Banshee.Library.Gui/ImportDialog.cs
@@ -165,7 +165,10 @@ namespace Banshee.Library.Gui
                     }
 
                     if (source != null) {
-                        source_model.SetValue (iter, 0, GetIcon (source));
+                        var icon = GetIcon (source);
+                        if (icon != null) {
+                            source_model.SetValue (iter, 0, icon);
+                        }
                     }
                 }
             }