* The old code in m_RangeMax/m_RangeMin setters wasn't doing proper
epsilon enforcing so min=max could end up happening. It's easier to
set both at once (this is all we care about anyway) so that it does
properly make the min and max distinguishable.
* This is the proper fix for 87bcde1c which is also more explicit about
what is going wrong. Thanks to the anonymous user who mentioned that they
clicked auto-fit before hitting the range histogram crash, which got me
on the right path to track down the exception!
* Crash report came in with System.OverflowException inside FillPolygon,
but I don't see a way for these values to get too large (or invalid
some other way).
baldurk