[pitivi] elements: Fix transitions tooltip

[Thibault Saunier <tsaunier src gnome org>]

commit da42fdc35109b4b9e430e662e84f1f0364c780f0
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Wed Dec 2 17:21:13 2015 +0100

    elements: Fix transitions tooltip
    
    Reviewed-by: Thibault Saunier <tsaunier gnome org>
    Differential Revision: https://phabricator.freedesktop.org/D574

 pitivi/timeline/elements.py |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/pitivi/timeline/elements.py b/pitivi/timeline/elements.py
index 4243df6..65c1570 100644
--- a/pitivi/timeline/elements.py
+++ b/pitivi/timeline/elements.py
@@ -979,7 +979,7 @@ class TransitionClip(Clip):
             markup = str(self.bClip.props.vtype.value_nick)
         else:
             markup = _("Audio crossfade")
-        self.set_tooltip_markup(markup)
+        tooltip.set_text(markup)
 
         return True