[meld] Discard output for git update-index calls (closes bgo#701687)

[Kai Willadsen <kaiw src gnome org>]

commit 477002f93cbe321e02b4ffa83f5869f27e1d35e2
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Sat Aug 24 08:53:18 2013 +1000

    Discard output for git update-index calls (closes bgo#701687)

 meld/vc/git.py |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/meld/vc/git.py b/meld/vc/git.py
index 90e05b5..7bb6ed6 100644
--- a/meld/vc/git.py
+++ b/meld/vc/git.py
@@ -263,8 +263,8 @@ class Vc(_vc.CachedVc):
     def _get_modified_files(self, path):
         # Update the index before getting status, otherwise we could
         # be reading stale status information
-        _vc.popen([self.CMD, "update-index", "--refresh"],
-                  cwd=self.location)
+        _vc.call([self.CMD, "update-index", "--refresh"],
+                 cwd=self.location)
 
         # Get the status of files that are different in the "index" vs
         # the HEAD of the git repository