[pitivi/1.0] utils: Emit selected-changed only when it changes

[Thibault Saunier <tsaunier src gnome org>]

commit 43407b6c81767fb1c78727dd827bcea1d6390e8e
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Sat Apr 28 09:30:19 2018 +0200

    utils: Emit selected-changed only when it changes
    
    It's more efficient this way, and it might fix #2087

 pitivi/utils/timeline.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
---
diff --git a/pitivi/utils/timeline.py b/pitivi/utils/timeline.py
index 91aedbfe..f6ab5da2 100644
--- a/pitivi/utils/timeline.py
+++ b/pitivi/utils/timeline.py
@@ -66,8 +66,10 @@ class Selected(GObject.Object):
 
     @selected.setter
     def selected(self, selected):
+        differs = self._selected != selected
         self._selected = selected
-        self.emit("selected-changed", selected)
+        if differs:
+            self.emit("selected-changed", selected)
 
 
 class Selection(GObject.Object, Loggable):