Summary:
Start migration of existing benchmarks to Google's Benchmark library + register benchmark to servicelab.
The benchmark should be automatically registered to servicelab once this diff lands according to https://www.internalfb.com/intern/wiki/ServiceLab/Use_Cases/Benchmarks_(C++)/#servicelab-job.
Reviewed By: mdouze
Differential Revision: D35397782
fbshipit-source-id: 317db2527f12ddde0631cacc3085c634afdd0e37