Since this is on Windows only, I'm also using the CriticalSectionWrapper and ConditionVariableWrapper Windows types directly which allows us to skip 3 extra heap allocations. It also helps with the removal of the 'friend' relationship between ConditionVariableWrapper and CriticalSectionWrapper, which is causing headaches on Mac.
BUG=
Review URL: https://codereview.webrtc.org/1595983002
Cr-Commit-Position: refs/heads/master@{#11300}