Bug fixed (reported by Maggesi): sometimes when the tactic had to generate new existential variables it failed. Fixing by propagating the metavariable environment generated by the unification.
Bug fixed (reported by Maggesi): sometimes when the tactic had to generate new
existential variables it failed. Fixing by propagating the metavariable
environment generated by the unification.


git-svn-id: 44dc50bdcc0f5d1a212c497508dc9452e0b35e2b@6215 85f007b7-540e-0410-9357-904b9bb8a0f7

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