This reverts commit 8039cdbe48.
Reason for revert: remove functionality after measurement complete
Original change's description:
> Measure wall clock time of capture and encode processing.
>
> (NOTE: This and dependent CLs will be reverted in a few days after
> data collection from the field is complete.)
>
> This change introduces a new task queue concept, Voucher. They
> are associated with a currently running task tree. Whenever
> tasks are posted, the current voucher is inherited and set as
> current in the new task.
>
> The voucher exists for as long as there are direct and indirect
> tasks running that descend from the task where the voucher was
> created.
>
> Vouchers aggregate application-specific attachments, which perform
> logic unrelated to Voucher progression. This particular change adds
> an attachment that measures time from capture to all encode operations
> complete, and places it into the WebRTC.Video.CaptureToSendTimeMs UMA.
>
> An accompanying Chrome change crrev.com/c/4992282 ensures survival of
> vouchers across certain Mojo IPC.
>
> Bug: chromium:1498378
> Change-Id: I2a27800a4e5504f219d8b9d33c56a48904cf6dde
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/325400
> Reviewed-by: Harald Alvestrand <hta@webrtc.org>
> Commit-Queue: Markus Handell <handellm@webrtc.org>
> Cr-Commit-Position: refs/heads/main@{#41061}
Bug: chromium:1498378
Change-Id: I9503575fbc52f1946ca26fc3c17b623ea75cd3c5
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/327023
Commit-Queue: Markus Handell <handellm@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Bot-Commit: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#41135}