This reverts commit 6b9c60b06d04bc519195fca1f621b10accfeb46b.
Reason for revert: Breaks downstream test
Original change's description:
> Removes lock release in PacedSender callback.
>
> The PacedSender currently has logic to temporarily release its internal
> lock while sending or asking for padding.
> This creates some tricky situations in the pacing controller where we
> need to consider if some thread can enter while we the process thread is
> actually processing, just temporarily busy sending.
>
> Since the pacing call stack is no longer cyclic, we can actually remove
> this lock-release now.
>
> Bug: webrtc:10809
> Change-Id: Ic59c605252bed1f96a03406c908a30cd1012f995
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/173592
> Reviewed-by: Sebastian Jansson <srte@webrtc.org>
> Commit-Queue: Erik Språng <sprang@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#31206}
TBR=sprang@webrtc.org,srte@webrtc.org
Change-Id: Ic84eee6097528d0792e3b1f90f36bc78447a0d81
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: webrtc:10809
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/174820
Reviewed-by: Erik Språng <sprang@webrtc.org>
Commit-Queue: Erik Språng <sprang@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31209}
3a65dba926