This reverts commit 06540166ca97028454adea48cec9bf109b771ddc.
Reason for revert: breaks downstream test.
Original change's description:
> Port: migrate to TaskQueue.
>
> Port uses legacy rtc::Thread message handling. In order
> to cancel callbacks it uses rtc::Thread::Clear() which uses locks and
> necessitates looping through all currently queued (unbounded) messages
> in the thread. In particular, these Clear calls are common during
> negotiation and the probability of having a lot of queued messages is
> high due to a long-running network thread function invoked on the
> network thread.
>
> Fix this by migrating Port to task queues.
>
>
> Bug: webrtc:12840, webrtc:9702
> Change-Id: I6c6fb83323899b56091f0857a1c2d15d19199002
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/221370
> Reviewed-by: Harald Alvestrand <hta@webrtc.org>
> Commit-Queue: Markus Handell <handellm@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#34338}
TBR=hta@webrtc.org,handellm@webrtc.org,webrtc-scoped@luci-project-accounts.iam.gserviceaccount.com
Change-Id: I014ef9267d224c10595cfa1c12899eabe0093306
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: webrtc:12840, webrtc:9702
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/223062
Reviewed-by: Markus Handell <handellm@webrtc.org>
Commit-Queue: Markus Handell <handellm@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#34339}
a4aabb9213