[pitivi] previewers: Simply use element URI to handle proxy/target thumbnail cache copying

[Thibault Saunier <tsaunier src gnome org>]

commit 57b6efe1fc6b7d74a3d154bb577cc2bb84d0f423
Author: Thibault Saunier <thibault saunier osg samsung com>
Date:   Thu Feb 9 10:51:29 2017 -0300

    previewers: Simply use element URI to handle proxy/target thumbnail cache copying
    
    In the case clips are DND onto the timeline the TrackElement might end
    up not being in a clip yet when we start processing it and we fail at
    retrieving its URI using its asset.
    
    Simply using the element 'uri' properties simplifies the logic.
    
    Fixes T7698
    
    Reviewed-by: Alex Băluț <alexandru balut gmail com>
    Differential Revision: https://phabricator.freedesktop.org/D1651

 pitivi/timeline/previewers.py |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/pitivi/timeline/previewers.py b/pitivi/timeline/previewers.py
index 946f802..2396dc0 100644
--- a/pitivi/timeline/previewers.py
+++ b/pitivi/timeline/previewers.py
@@ -687,10 +687,10 @@ class VideoPreviewer(Previewer, Zoomable, Loggable):
         self._startThumbnailingWhenIdle()
 
     def _ensure_proxy_thumbnails_cache(self):
-        """Ensures that both the target asset and the proxy assets have caches"""
-        asset_uri = quote_uri(self.ges_elem.get_parent().get_asset().props.id)
-        if self.uri != asset_uri:
-            self.thumb_cache.copy(asset_uri)
+        """Ensures that both the target asset and the proxy assets have caches."""
+        uri = self.ges_elem.props.uri
+        if self.uri != uri:
+            self.thumb_cache.copy(uri)
 
     def stopGeneration(self):
         if self._thumb_cb_id: