Revert "Implement RtpParameters.transaction_id for PC RtpSenderInterface"

This reverts commit 5faf36ef3c582350fba5ef97a3549e440d81a283.

Reason for revert: fast/peerconnection/RTCRtpSender-setParameters.html
 failing in webrtc roll, probably this CL? https://chromium-review.googlesource.com/c/chromium/src/+/1045889.

Original change's description:
> Implement RtpParameters.transaction_id for PC RtpSenderInterface
> 
> The transaction_id field should be refreshed for every getParameters()
> call and checked at each setParameters() call.
> This also checks that getParameters() was ever called to return a proper
> error code.
> 
> Bug: webrtc:7580
> Change-Id: I6c6fe289542e486fc422cdc61577982b0529d4c1
> Reviewed-on: https://webrtc-review.googlesource.com/70820
> Commit-Queue: Florent Castelli <orphis@webrtc.org>
> Reviewed-by: Sami Kalliomäki <sakal@webrtc.org>
> Reviewed-by: Taylor Brandstetter <deadbeef@webrtc.org>
> Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
> Reviewed-by: Steve Anton <steveanton@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#23120}

TBR=steveanton@webrtc.org,deadbeef@webrtc.org,sakal@webrtc.org,kthelgason@webrtc.org,orphis@webrtc.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: webrtc:7580
Change-Id: I86da108227f8fc8d235bb2e9559377c800595b8c
Reviewed-on: https://webrtc-review.googlesource.com/74740
Reviewed-by: Max Morin <maxmorin@webrtc.org>
Commit-Queue: Max Morin <maxmorin@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23134}
diff --git a/api/rtpparameters.h b/api/rtpparameters.h
index e8ff116..12e0419 100644
--- a/api/rtpparameters.h
+++ b/api/rtpparameters.h
@@ -546,6 +546,7 @@
   // Used when calling getParameters/setParameters with a PeerConnection
   // RtpSender, to ensure that outdated parameters are not unintentionally
   // applied successfully.
+  // TODO(deadbeef): Not implemented.
   std::string transaction_id;
 
   // Value to use for MID RTP header extension.