[luatex] some bits of opentype math testing

[taco]

Khaled Hosny wrote:
> 
>> Rendering issues (ConTeXt and LuaLaTeX):
>>
>> - Asana-Math displaystyle delimiters appear in extensible version
>>   -> open, unresolved, possibly also a font bug
> 
> I think it might be an engine issue, I recall having the same problem
> with Neo Euler until I disable the extensible integrals (I think other
> fonts have no extensible integrals so the issue is hidden).

Is there a small test file for this (preferably in ConTeXt or
plain luatex?)

Best wishes,
Taco