Revert "bug #187 Ensure hrtime is monotonic (GrahamCampbell)"
Revert "bug #187 Ensure hrtime is monotonic (GrahamCampbell)"

This reverts commit 64d2d7d5b4595443c1ad0c667597ea4f5ae1e7a5, reversing
changes made to b501e55fbc45de6bc4112efeb7cb5f4b6a283d7b.

symfony/polyfill,nicolas-grekas/polyfill