Fix all-fire context for conditional effects

[haz]

This code should be disabled for now, and then rethought: https://github.com/QuMuLab/pr2/blob/main/src/deadend.cc#L120

It's rarely used (requires a domain with conditional effects), and actually is buggy in the following situation:

(oneof
  (when (...) (...))
  (when (...) (...))
  ...
)

The all-fire context is computed for each determinized operator (unlike the conditional mask, which is computed for the full non-det operator), and it's only used for the regression of generalized deadends. It was a minor hack (unpublished) that let us gain a few more FSAPs in certain corner cases, and worked when the conditional effects were not nested within the oneof clauses. It's current implementation is incorrect when the condeffs are inside the oneof, as above -- result is an FSAP potentially being created that is too "strong" (rules out things it shouldn't).

[haz]

Minimal broken example...

domain.pddl.txt
problem.pddl.txt