[gnome-boxes] installer: Add try to delete inexistant file

[Zeeshan Ali Khattak <zeeshanak src gnome org>]

commit 4bca0198f0ba4d8bf7a8d1d051b69d415ece3e7a
Author: Zeeshan Ali (Khattak) <zeeshanak gnome org>
Date:   Wed Dec 5 17:49:24 2012 +0200

    installer: Add try to delete inexistant file
    
    Don't try to delete the temporary file if it wasn't created.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=676537

 src/unattended-installer.vala |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)
---
diff --git a/src/unattended-installer.vala b/src/unattended-installer.vala
index d1f2da6..8b260b0 100644
--- a/src/unattended-installer.vala
+++ b/src/unattended-installer.vala
@@ -688,6 +688,9 @@ private class Boxes.UnattendedTextFile : GLib.Object, Boxes.UnattendedFile {
     }
 
     ~UnattendedTextFile () {
+        if (unattended_tmp == null)
+            return;
+
         try {
             delete_file (unattended_tmp);
         } catch (GLib.Error e) {
@@ -746,6 +749,9 @@ private class Boxes.UnattendedAvatarFile : GLib.Object, Boxes.UnattendedFile {
     }
 
     ~UnattendedAvatarFile () {
+        if (unattended_tmp == null)
+            return;
+
         try {
             delete_file (unattended_tmp);
         } catch (GLib.Error e) {