[gnome-builder] todo: disconnect buffer manager signal

[Christian Hergert <chergert src gnome org>]

commit 789fe992a6edbe30b7bb08d8665d8b719ce6542e
Author: Christian Hergert <chergert redhat com>
Date:   Tue Aug 16 18:05:15 2016 +0200

    todo: disconnect buffer manager signal

 plugins/todo/todo_plugin/__init__.py |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)
---
diff --git a/plugins/todo/todo_plugin/__init__.py b/plugins/todo/todo_plugin/__init__.py
index e909cc5..7f2530a 100644
--- a/plugins/todo/todo_plugin/__init__.py
+++ b/plugins/todo/todo_plugin/__init__.py
@@ -59,12 +59,17 @@ class TodoWorkbenchAddin(GObject.Object, Ide.WorkbenchAddin):
 
         # Watch the buffer manager for file changes (to update)
         bufmgr = context.get_buffer_manager()
-        bufmgr.connect('buffer-saved', self.on_buffer_saved)
+        self.buffer_saved_handler = bufmgr.connect('buffer-saved', self.on_buffer_saved)
 
         # Mine the directory in a background thread
         self.mine(workdir)
 
     def do_unload(self, workbench):
+        context = workbench.get_context()
+
+        bufmgr = context.get_buffer_manager()
+        bufmgr.disconnect(self.buffer_saved_handler)
+
         self.panel.destroy()
         self.panel = None