[PATCH 4 of 7 evolve-ext] evolve: fix crash in _orderrevs

[timeless at gcc2-power8.osuosl.org]

# HG changeset patch
# User timeless at gmail.com
# Date 1460605333 0
#      Thu Apr 14 03:42:13 2016 +0000
# Node ID 48cb89ebf3625ad386be7d1941b725b8e64d5db9
# Parent  6d5f4ff81952cbc23f196b60bcd298495b99e5e3
# Available At https://bitbucket.org/timeless/mutable-history/
#              hg pull https://bitbucket.org/timeless/mutable-history/ -r 48cb89ebf362
evolve: fix crash in _orderrevs

diff -r 6d5f4ff81952 -r 48cb89ebf362 hgext/evolve.py
--- a/hgext/evolve.py	Wed Apr 13 23:36:44 2016 +0000
+++ b/hgext/evolve.py	Thu Apr 14 03:42:13 2016 +0000
@@ -1509,7 +1509,8 @@
     while solvablerevs:
         rev = solvablerevs.popleft()
         for dependent in rdependencies[rev]:
-            dependencies[dependent].remove(rev)
+            if rev in dependencies[dependent]:
+                dependencies[dependent].remove(rev)
             if not dependencies[dependent]:
                 solvablerevs.append(dependent)
         del dependencies[rev]