WPT import https://crrev.com/c/1377724 introduced new failures in external/wpt/webrtc:

List of new failures:
virtual/webrtc-wpt-unified-plan/external/wpt/webrtc/RTCPeerConnection-setDescription-transceiver.html new failing tests: https://crrev.com/c/1377724/4/third_party/blink/web_tests/virtual/webrtc-wpt-unified-plan/external/wpt/webrtc/RTCPeerConnection-setDescription-transceiver-expected.txt
external/wpt/webrtc/RTCPeerConnection-setDescription-transceiver.html new failing tests: https://crrev.com/c/1377724/4/third_party/blink/web_tests/external/wpt/webrtc/RTCPeerConnection-setDescription-transceiver-expected.txt
external/wpt/webrtc/RTCPeerConnection-setDescription-transceiver.html new failing tests: https://crrev.com/c/1377724/4/third_party/blink/web_tests/virtual/webrtc-wpt-unified-plan/external/wpt/webrtc/RTCPeerConnection-setDescription-transceiver-expected.txt

This import contains upstream changes from 04c862e10e0774beb17dbf84d94743a788d94bfc to 1db8f79ee94cf257617cbf470c6dcf7e0bbdcab5:
WebKit export of https://bugs.webkit.org/show_bug.cgi?id=192685 (#14516): https://github.com/web-platform-tests/wpt/commit/1db8f79ee94cf257617cbf470c6dcf7e0bbdcab5 [affecting this directory]
clear.py relies on old Gecko's <button> hit testing: https://github.com/web-platform-tests/wpt/commit/c85f06ed9124feda30aed89914529bdd60d0fb80
Return used width/height for SVG <image>, <rect> and <foreignObject>: https://github.com/web-platform-tests/wpt/commit/e75e7b667c75aabc4569b46d902b81d40d9b8e44