Javadoc
Given the set of NFA states in DFA state d, find all NFA states
reachable traversing label arcs. By definition, there can be
only one DFA state reachable by an atom from DFA state d so we must
find and merge all NFA states reachable via label. Return a new
DFAState that has all of those NFA states with their context (i.e.,
which alt do they predict and where to return to if they fall off
end of a rule).
Because we cannot jump to another rule nor fall off the end of a rule
via a non-epsilon transition, NFA states reachable from d have the
same configuration as the NFA state in d. So if NFA state 7 in d's
configurations can reach NFA state 13 then 13 will be added to the
new DFAState (labelDFATarget) with the same configuration as state
7 had.
This method does not see EOT transitions off the end of token rule
accept states if the rule was invoked by somebody.