[gitg/highlighting] Do not print cancelled errors

[Jesse van den Kieboom <jessevdk src gnome org>]

commit d578ad0b25fcef78aa70064dca62cf70f33b9222
Author: Jesse van den Kieboom <jessevdk gnome org>
Date:   Wed Dec 23 01:03:48 2015 +0100

    Do not print cancelled errors

 libgitg/gitg-diff-view-file.vala |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)
---
diff --git a/libgitg/gitg-diff-view-file.vala b/libgitg/gitg-diff-view-file.vala
index 395f467..d0012e8 100644
--- a/libgitg/gitg-diff-view-file.vala
+++ b/libgitg/gitg-diff-view-file.vala
@@ -383,7 +383,11 @@ class Gitg.DiffViewFile : Gtk.Grid
                }
                catch (Error e)
                {
-                       stderr.printf(@"ERROR: failed to load $(file.get_path()) for highlighting: 
$(e.message)\n");
+                       if (!cancellable.is_cancelled())
+                       {
+                               stderr.printf(@"ERROR: failed to load $(file.get_path()) for highlighting: 
$(e.message)\n");
+                       }
+
                        return null;
                }