Enable expression complexity limits.
Enable expression complexity limits.

Fixes a stack-overflow crash in long-expressions-should-not-crash.html
on newer Mesa, and apparently also on (at least older) NVIDIA drivers.

This defaults to angle's default "256".  Firefox seems to do 1000 for
the NVIDIA bug and not cover Mesa.

ecoal95/angle,ecoal95/angle,ecoal95/angle,ecoal95/angle,ecoal95/angle