Summary:
I tried switching Flipper to use the node.js module: https://nodejs.org/api/perf_hooks.html instead of electrons window.performance. But the module couldn't be found.
So instead, I'm just replacing it in the pure node tests.
This means tests without node can work without issues.
Reviewed By: danielbuechele
Differential Revision: D10302114
fbshipit-source-id: b3b8aa5fb350a8246fcdfc2a80cc72daec2448d7
