[pitivi] utils/widgets: Only reset keyframes if there are keyframes.

[Jean-François Fortin Tam <jfft src gnome org>]

commit 4d40fd24a815ec41c68845cd416b01e6b84fadb0
Author: Mathieu Duponchelle <mathieu duponchelle epitech eu>
Date:   Mon Jul 8 01:37:33 2013 +0200

    utils/widgets: Only reset keyframes if there are keyframes.

 pitivi/utils/widgets.py |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)
---
diff --git a/pitivi/utils/widgets.py b/pitivi/utils/widgets.py
index 75ebd82..009c857 100644
--- a/pitivi/utils/widgets.py
+++ b/pitivi/utils/widgets.py
@@ -971,7 +971,10 @@ class GstElementSettingsWidget(Gtk.VBox, Loggable):
                 track_element.ui_element.hideKeyframes()
 
     def _defaultBtnClickedCb(self, button, widget):
-        binding = self.bindings[widget]
+        try:
+            binding = self.bindings[widget]
+        except KeyError:
+            binding = None
         if binding:
             effect = self.element
             track_type = effect.get_track_type()