[text-spacing-trim] Implement line-end logic · web-platform-tests/wpt@05918d6

Firefox results

Results have successfully been scraped and added to staging.wpt.fyi.

Uh-oh - it looks like there are some newly-failing results when we compared the affected tests
to the latest run against the master branch.

Run	Spec
`master`	firefox-123.0a1-linux-20.04@be1b4f8c3a
`05918d6`	firefox-123.0a1-linux-20.04@05918d61fb

Test	`master`	`05918d6`
/html/browsers/browsing-the-web/navigating-across-documents/initial-empty-document/iframe-src-204-fragment.html	2 / 5	0 / 5
/html/infrastructure/safe-passing-of-structured-data/shared-array-buffers/blob-data.https.html	17 / 18	17 / 19
/html/semantics/invokers/invoketarget-on-video-behavior.tentative.html	7 / 13	6 / 13
/html/semantics/scripting-1/the-script-element/moving-between-documents/after-prepare-iframe-fetch-error-external-module.html	5 / 5	4 / 5
/html/syntax/speculative-parsing/generated/page-load/img-srcset.tentative.html	1 / 1	0 / 1
/navigation-timing/test-timing-attributes-dependent-on-document-load.html	1 / 1	0 / 1
/storage-access-api/hasStorageAccess-insecure.sub.window.html	15 / 15	15 / 16
/svg/animations/scripted/onhover-syncbases.html	1 / 1	0 / 1
/webrtc/RTCDataChannel-close.html	2 / 10	1 / 11
/webrtc/RTCDataChannel-iceRestart.html	2 / 2	2 / 3
/webrtc/RTCRtpReceiver-getStats.https.html	2 / 5	1 / 5