when using DelegatingRefiner, or more generally, having two different refiners refining different precisions independently from each other, it may happen that one refiner voids precisions the other has added before; this commit fixes this when using refinement for the value and predicate analysis, e.g., when using the ValueAnalysisDelegatingRefiner

git-svn-id: https://svn.sosy-lab.org/software/cpachecker/trunk@14824 4712c6d2-40bb-43ae-aa4b-fec3f1bdfe4c