[pitivi] previewers: Expect the keys method to return an iterable

[Mathieu Duponchelle <mathieudu src gnome org>]

commit 340fb585e0c835920af855d118004ca0cba0957b
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Sun Dec 8 11:01:40 2013 +0100

    previewers: Expect the keys method to return an iterable

 pitivi/timeline/previewers.py |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)
---
diff --git a/pitivi/timeline/previewers.py b/pitivi/timeline/previewers.py
index 92691b5..99c0be3 100644
--- a/pitivi/timeline/previewers.py
+++ b/pitivi/timeline/previewers.py
@@ -393,8 +393,7 @@ class VideoPreviewer(Clutter.ScrollActor, PreviewGenerator, Zoomable, Loggable):
         if time in self.thumbs:
             self.thumbs[time].set_from_gdkpixbuf_animated(pixbuf)
         else:
-            sorted_times = self.thumbs.keys()
-            sorted_times.sort()
+            sorted_times = sorted(self.thumbs.keys())
             index = binary_search(sorted_times, time)
             time = sorted_times[index]
             thumb = self.thumbs[time]