Submitted by 0xRajeev, also found by cmichel and gpersoon
The gas cost for liquidation may change if code is updated/optimized, the compiler is changed or profiling is improved. The developers may forget to update this constant in code. The impact is that the margin validity calculation, which uses this value, may be affected if this changes and hence is not as declared in the constant. This may adversely impact validation.
Because It is safer to make this a constructor-set immutable value that will force usage of an updated accurate value at deployment time.
Recommend evaluating if the sensitivity to this value is great enough to justify a setter to change it if incorrectly initialized at deployment.
raymogg (Tracer) confirmed in (duplicate issue)
