Revert "Reland "Adds support for multiple or no media stream ids.""

This reverts commit f351c3408a0c7f695447a2a9f4e6a1719a0d6a26.

Reason for revert: Breaks chromium import

https://ci.chromium.org/p/chromium/builders/luci.chromium.try/linux_chromium_rel_ng/58012

Failin tests:
WebRtcRtpBrowserTest.TrackAddedToSecondStream
WebRtcRtpBrowserTest.TrackSwitchingStream

Original change's description:
> Reland "Adds support for multiple or no media stream ids."
> 
> This is a reland of 1550292efe680ac79a18004705c908b1cdca54cb
> 
> Original change's description:
> > Adds support for multiple or no media stream ids.
> > 
> > With Unified Plan SDP semantics, this adds support for specifying
> > either no media stream ids or multiple media stream ids for a
> > transceiver/sender/receiver. This includes serializing/deserializing
> > SDPs with multiple a=msid lines in a m section, or an "a=msid:-
> > <appdata>" line to indicate the no stream case. Note that this does
> > not synchronize between multiple streams, this is still just supported
> > based upon the first media stream id.
> > 
> > Bug: webrtc:7932, webrtc:7933
> > Change-Id: Ib7433929af7b2925abe2824b485b360cec12f275
> > Reviewed-on: https://webrtc-review.googlesource.com/61341
> > Commit-Queue: Seth Hampson <shampson@webrtc.org>
> > Reviewed-by: Taylor Brandstetter <deadbeef@webrtc.org>
> > Reviewed-by: Steve Anton <steveanton@webrtc.org>
> > Cr-Commit-Position: refs/heads/master@{#22611}
> 
> Bug: webrtc:7932, webrtc:7933
> Change-Id: Ica272ac18088103e65cccf6b96a6d3ecccb178ed
> Reviewed-on: https://webrtc-review.googlesource.com/65560
> Commit-Queue: Seth Hampson <shampson@webrtc.org>
> Reviewed-by: Taylor Brandstetter <deadbeef@webrtc.org>
> Reviewed-by: Steve Anton <steveanton@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#22687}

TBR=steveanton@webrtc.org,deadbeef@webrtc.org,shampson@webrtc.org

Change-Id: I1835419f963762bc308a91d81c423d8e7bf65026
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: webrtc:7932, webrtc:7933
Reviewed-on: https://webrtc-review.googlesource.com/65700
Reviewed-by: Tomas Gunnarsson <tommi@chromium.org>
Commit-Queue: Tomas Gunnarsson <tommi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#22690}

api/rtptransceiverinterface.h

@@ -40,6 +40,9 @@ struct RtpTransceiverInit final {
   RtpTransceiverDirection direction = RtpTransceiverDirection::kSendRecv;
 
   // The added RtpTransceiver will be added to these streams.
+  // TODO(shampson): Change name to stream_id & update native wrapper's naming
+  // as well.
+  // TODO(bugs.webrtc.org/7600): Not implemented.
   std::vector<std::string> stream_ids;
 
   // TODO(bugs.webrtc.org/7600): Not implemented.