Revert "Fix RTCPeerConnection-track-stats.https.html expectations."

This reverts commit bae1ec12.

Reason for revert: Causing failures on Linux Tests bot: https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Linux%20Tests/74581

Original change's description:
> Fix RTCPeerConnection-track-stats.https.html expectations.
> 
> The tests started failing in an earlier WPT import, see
> https://crbug.com/832501.
> 
> TBR=hta@chromium.org
> 
> Bug: 832501
> Change-Id: If53c927e03dabb60158c61befc5a29d1c45bba1f
> Reviewed-on: https://chromium-review.googlesource.com/c/1394307
> Reviewed-by: Henrik Boström <hbos@chromium.org>
> Commit-Queue: Henrik Boström <hbos@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#619631}

TBR=hbos@chromium.org

Change-Id: I6b02e4b99e003b1ee1e686eea1bf3b36aadb4b39
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 832501
Reviewed-on: https://chromium-review.googlesource.com/c/1394705Reviewed-by: Tommy Steimel <steimel@chromium.org>
Commit-Queue: Tommy Steimel <steimel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#619672}

third_party/blink/web_tests/TestExpectations

@@ -3208,6 +3208,10 @@ crbug.com/893490 [ Mac ] external/wpt/css/css-text/white-space/control-chars-09F
 crbug.com/893480 external/wpt/infrastructure/testdriver/actions/elementTiming.html [ Timeout ]
 crbug.com/893480 external/wpt/infrastructure/testdriver/actions/multiDevice.html [ Failure Timeout ]
 
+# wpt-importer has trouble rebaselining these tests. They might be flaky?
+crbug.com/832501 external/wpt/webrtc/RTCPeerConnection-track-stats.https.html [ Failure ]
+crbug.com/832501 virtual/webrtc-wpt-unified-plan/external/wpt/webrtc/RTCPeerConnection-track-stats.https.html [ Failure ]
+
 # Hit a DCHECK
 crbug.com/918664 external/wpt/css/vendor-imports/mozilla/mozilla-central-reftests/sizing/block-size-with-min-or-max-content-table-1a.html [ Failure Pass ]
 

third_party/blink/web_tests/external/wpt/webrtc/RTCPeerConnection-track-stats.https-expected.txt

-This is a testharness.js-based test.
-PASS addTrack() without setLocalDescription() yields track stats
-PASS addTrack() without setLocalDescription() yields media stream stats
-PASS addTrack() with setLocalDescription() yields track stats
-PASS addTrack() with setLocalDescription() yields media stream stats
-PASS addTrack(): Media stream stats references track stats
-PASS Media stream stats references track stats
-PASS O/A exchange yields outbound RTP stream stats for sending track
-PASS O/A exchange yields inbound RTP stream stats for receiving track
-PASS replaceTrack() before offer: new track attachment stats present
-PASS replaceTrack() after offer, before answer: new track attachment stats present
-PASS replaceTrack() after answer: new track attachment stats present
-FAIL replaceTrack(): original track attachment stats present after replacing assert_true: Has stats for original track expected true got false
-PASS RTCRtpSender.getStats() contains only outbound-rtp and related stats
-PASS RTCRtpReceiver.getStats() contains only inbound-rtp and related stats
-PASS RTCPeerConnection.getStats(sendingTrack) is the same as RTCRtpSender.getStats()
-PASS RTCPeerConnection.getStats(receivingTrack) is the same as RTCRtpReceiver.getStats()
-PASS RTCPeerConnection.getStats(track) throws InvalidAccessError when there are zero senders or receivers for the track
-PASS RTCPeerConnection.getStats(track) throws InvalidAccessError when there are multiple senders for the track
-Harness: the test ran to completion.
-