[f-spot] Truncate stream when writing sidecar XMP files.

[Ruben Vermeersch <rubenv src gnome org>]

commit e0e7e474f15c4f0c2e01c2fd66b077bd02250075
Author: Ruben Vermeersch <ruben savanne be>
Date:   Fri Jul 2 23:51:57 2010 +0200

    Truncate stream when writing sidecar XMP files.

 src/Utils/SidecarXmpExtensions.cs |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/src/Utils/SidecarXmpExtensions.cs b/src/Utils/SidecarXmpExtensions.cs
index ed8f53c..aac3f11 100644
--- a/src/Utils/SidecarXmpExtensions.cs
+++ b/src/Utils/SidecarXmpExtensions.cs
@@ -36,6 +36,7 @@ namespace FSpot.Utils
             var xmp = xmp_tag.Render ();
 
             using (var stream = resource.WriteStream) {
+                stream.SetLength (0);
                 using (var writer = new StreamWriter (stream)) {
                     writer.Write (xmp);
                 }