[pitivi/gtktimeline] timeline: Properly clear layer.ui when removing a layer

[Thibault Saunier <tsaunier src gnome org>]

commit 917acec474d36c22723a730cf02eee34d8e7bb1b
Author: Thibault Saunier <tsaunier gnome org>
Date:   Sat May 16 11:04:54 2015 +0200

    timeline: Properly clear layer.ui when removing a layer
    
    Fixes http://phabricator.freedesktop.org/T62

 pitivi/timeline/layer.py    |    7 +++++++
 pitivi/timeline/timeline.py |    1 +
 2 files changed, 8 insertions(+), 0 deletions(-)
---
diff --git a/pitivi/timeline/layer.py b/pitivi/timeline/layer.py
index 975331c..2f64b59 100644
--- a/pitivi/timeline/layer.py
+++ b/pitivi/timeline/layer.py
@@ -525,6 +525,12 @@ class Layer(Gtk.EventBox, timelineUtils.Zoomable, Loggable):
         self.before_sep = None
         self.after_sep = None
 
+    def release(self):
+        for clip in self.bLayer.get_clips():
+            self._removeClip(clip)
+        self.bLayer.disconnect_by_func(self._clipAddedCb)
+        self.bLayer.disconnect_by_func(self._clipRemovedCb)
+
     def checkMediaTypes(self, bClip=None):
         if self.timeline.editing_context:
             self.info("Not updating media types as"
@@ -604,6 +610,7 @@ class Layer(Gtk.EventBox, timelineUtils.Zoomable, Loggable):
             return
 
         self._layout.remove(bClip.ui)
+        bClip.ui.layer = None
         if self.timeline.draggingElement is None:
             bClip.ui = None
 
diff --git a/pitivi/timeline/timeline.py b/pitivi/timeline/timeline.py
index 0a40a2a..7cdd46b 100644
--- a/pitivi/timeline/timeline.py
+++ b/pitivi/timeline/timeline.py
@@ -777,6 +777,7 @@ class Timeline(Gtk.EventBox, timelineUtils.Zoomable, Loggable):
         self.__layers_controls_vbox.remove(bLayer.control_ui)
 
         self._layers.remove(bLayer.ui)
+        bLayer.ui.release()
         bLayer.ui = None
         bLayer.control_ui = None