ASSERT_CE_APPROX_EQUAL is a thin wrapper on top of ASSERT_APPROX_EQUAL. It converts a CE value to double (via static_cast<double>) before comparing. This is used by previous CEType (defunct) and does not work with new strong type alias CardinalityEstimate any more. All the uses of ASSERT_CE_APPROX_EQUAL already have operands as doubles and we should simply use ASSERT_APPROX_EQUAL.

Remove ASSERT_CE_APPROX_EQUAL and replace all the call sites with ASSERT_APPROX_EQUAL.