...making Fraction::HasOverflowValue() always return false on all platforms,
regardless of size of long, since 331e2e5e
"long->sal_Int32 in Fraction" changed Fraction::Impl::value from
boost::rational<sal_Int64> to boost::rational<sal_Int32>, and changed the limits
to compare with in Fraction::HasOverflowValue from long to sal_Int32.

Change-Id: I226ca240d6092ac803a1f65a363b1384903da17a