Resync web-platform-tests/picture-in-picture from upstream.
Created attachment 404608 [details] Patch
This patch modifies the imported WPT tests. Please ensure that any changes on the tests (not coming from a WPT import) are exported to WPT. Please see https://trac.webkit.org/wiki/WPTExportProcess
Comment on attachment 404608 [details] Patch r=me
Committed r264559: <https://trac.webkit.org/changeset/264559> All reviewed patches have been landed. Closing bug and clearing flags on attachment 404608 [details].
<rdar://problem/65751146>