Summary: sleeping in the measure function was done to ensure we were not regressing in double measure calls. This was before we have CSSLayoutMeasureCacheTest though. Let's switch over benchmark to purely benchmark the algorithm and not simulate measure time. Reviewed By: swolchok Differential Revision: D4078186 fbshipit-source-id: e1c16806b3c8714e223e1cfcb6c43846f8f6bbb2