moved addsplits [expand_if] from HOL_basic_ss to HOL_ss;
moved addsplits [expand_if] from HOL_basic_ss to HOL_ss;

MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle