volume_integral_kernel! for DGMulti

[DanielDoehring]

See #2802 (comment)

[github-actions]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.10%. Comparing base (2a047dc) to head (7f0ceb8).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2809      +/-   ##
==========================================
+ Coverage   97.09%   97.10%   +0.01%     
==========================================
  Files         589      589              
  Lines       45536    45539       +3     
==========================================
+ Hits        44211    44218       +7     
+ Misses       1325     1321       -4     

Flag	Coverage Δ
unittests	97.10% <100.00%> (+0.01%)	⬆️

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[jlchan]

Thanks for refactoring this!

[ranocha]

Isn't this now called for every element, making it much more expensive?

[DanielDoehring]

Oh yeah absolutely right. I opened a fix: #2812

[jlchan]

Can't believe I missed that...

[ranocha]

Same here