[pitivi] Make PropertyChangeTracker add signals to itself for the signals it's proxying.

[Edward Hervey <edwardrv src gnome org>]

commit a45a7db8cee90c83fd8922200f9a558d5598ca88
Author: Alessandro Decina <alessandro d gmail com>
Date:   Wed Jun 10 13:38:16 2009 +0200

    Make PropertyChangeTracker add signals to itself for the signals it's proxying.

 pitivi/utils.py |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/pitivi/utils.py b/pitivi/utils.py
index b1c067a..43d4e54 100644
--- a/pitivi/utils.py
+++ b/pitivi/utils.py
@@ -243,9 +243,11 @@ class PropertyChangeTracker(Signallable):
     def connectToObject(self, obj):
         for property_name in self.property_names:
             self.properties[property_name] = \
-                    getattr(obj, property_name)
+                    getattr(obj, property_name.replace("-", "_"))
 
-            obj.connect(property_name + '-changed',
+            signal_name = property_name + '-changed'
+            self.__signals__[signal_name] = []
+            obj.connect(signal_name,
                     self._propertyChangedCb, property_name)