diff -r ca5ca3badd3c -r 05c80f9ef100 mercurial/revlogutils/flagutil.py
--- a/mercurial/revlogutils/flagutil.py	Thu Aug 08 01:03:01 2019 +0200
+++ b/mercurial/revlogutils/flagutil.py	Thu Aug 08 01:04:48 2019 +0200
@@ -28,4 +28,8 @@
 REVIDX_KNOWN_FLAGS
 REVIDX_RAWTEXT_CHANGING_FLAGS
 
+# Store flag processors (cf. 'addflagprocessor()' to register)
+flagprocessors = {
+    REVIDX_ISCENSORED: None,
+}