Many CPAs use an implementation of areAbstractSuccessors
that passes null as precision to getAbstractSuccessors.
This would break if these transfer relations would actually use the
precision object, so we pass a dummy precision instead.

git-svn-id: https://svn.sosy-lab.org/software/cpachecker/trunk@13434 4712c6d2-40bb-43ae-aa4b-fec3f1bdfe4c