[meld/Python3] meldbuffer: Avoid tuple comparison with None for py3k (bgo#768407)

[Kai Willadsen <kaiw src gnome org>]

commit 6be761c5ab38a3f2e390336e158986b9e7f6ad5a
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Sun Jul 10 09:43:11 2016 +1000

    meldbuffer: Avoid tuple comparison with None for py3k (bgo#768407)

 meld/meldbuffer.py |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/meld/meldbuffer.py b/meld/meldbuffer.py
index b7d1d42..186d624 100644
--- a/meld/meldbuffer.py
+++ b/meld/meldbuffer.py
@@ -162,7 +162,7 @@ class MeldBufferData(GObject.GObject):
 
     def _handle_file_change(self, monitor, f, other_file, event_type):
         mtime = self._query_mtime(f)
-        if self._disk_mtime and mtime > self._disk_mtime:
+        if self._disk_mtime and mtime and mtime > self._disk_mtime:
             self.emit('file-changed')
         self._disk_mtime = mtime