While transitioning over to rtc::CriticalSection completely, this gives perf benefits that rtc::CriticalSection has on Mac to current users of CriticalSectionWrapper.
BUG=
Review URL: https://codereview.webrtc.org/1614373002
Cr-Commit-Position: refs/heads/master@{#11356}
There's no need for this class to have a vtable since there exists only a single implementation (per platform). It's also not good for performance.
BUG=
R=pbos@webrtc.org
Review URL: https://codereview.webrtc.org/1601743004 .
Cr-Commit-Position: refs/heads/master@{#11306}