Fix compiler common check speed for many polygons

[tdhock]

Closes #235

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 77.67%. Comparing base (e32921c) to head (3095077).
⚠️ Report is 12 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #238      +/-   ##
==========================================
- Coverage   77.68%   77.67%   -0.02%     
==========================================
  Files         164      164              
  Lines        8803     8799       -4     
  Branches      572      560      -12     
==========================================
- Hits         6839     6835       -4     
  Misses       1964     1964              

Flag	Coverage Δ
javascript	95.36% <ø> (ø)
r	69.50% <100.00%> (-0.03%)	⬇️

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