--- a/mercurial/unionrepo.py	Tue Oct 18 14:27:30 2016 -0500
+++ b/mercurial/unionrepo.py	Tue Oct 18 17:32:51 2016 -0700
@@ -208,8 +208,7 @@
         node = self.repo2.changelog.node(rev2)
         return self.changelog.rev(node)
 
-    @localrepo.unfilteredpropertycache
-    def manifest(self):
+    def _constructmanifest(self):
         return unionmanifest(self.svfs, self.repo2.svfs,
                              self.unfiltered()._clrev)