436 Does not complain about new head if you obsolete the old one

   437 

   438   $ hg push ../other-new --traceback

   439   pushing to ../other-new

   440   searching for changes

   441   adding changesets

   442   adding manifests

   443   adding file changes

   444   added 2 changesets with 1 changes to 1 files

   445   83b5778897ad try to obsolete immutable changeset 1f0dee641bb7

   446   $ hg up -q 10

   447   $ mkcommit "obsol_d'''"

   448   created new head

   449   $ hg debugobsolete 12 11

   450   $ hg push ../other-new --traceback

   451   pushing to ../other-new

   452   searching for changes

   453   adding changesets

   454   adding manifests

   455   adding file changes

   456   added 1 changesets with 1 changes to 1 files (+1 heads)