Bug 1552755 - Update video_capture/windows code to tip of webrtc.org; r=ng

This updates just video_capture/windows to the tip of webrtc.org, from commit
8581877121f58435d683c2a39a73e72e5dcd558a.

This removes the locking which was leading to the deadlock in Bug 1552755. It
also removes the reliance upon the DirectShow example code which lead to our
local implementations of BaseFilter, BaseInputPin, BasePin, and MediaType.
These can now be removed.

Differential Revision: https://phabricator.services.mozilla.com/D33336

--HG--
extra : moz-landing-system : lando