[pitivi] render: Make sure the to actually set restriction caps

[Thibault Saunier <tsaunier src gnome org>]

commit 570463826f96fd0c9a9efb4df1eb2ff6ba9fac55
Author: Thibault Saunier <tsaunier gnome org>
Date:   Mon Jun 1 15:58:48 2015 +0200

    render: Make sure the to actually set restriction caps
    
    We were setting the video format on caps that were actually copied.
    This is due to a 'recent' behaviour in PyGObject.

 pitivi/render.py |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)
---
diff --git a/pitivi/render.py b/pitivi/render.py
index bdf4299..9754b3d 100644
--- a/pitivi/render.py
+++ b/pitivi/render.py
@@ -942,8 +942,7 @@ class RenderDialog(Loggable):
                     caps = Gst.Caps.from_string(struct.get_caps().to_string())
                     fixed = caps.fixate()
                     fmt = fixed.get_structure(0).get_value("format")
-                    self.project.video_profile.get_restriction()[
-                        0]["format"] = fmt
+                    self.project.set_video_restriction_value("format", fmt)
                     self._factory_formats[encoder_string] = fmt
                     break