src/third_party/web_platform_tests/conformance-checkers/html/elements/picture/always-matching-source-media-all-spaces-with-following-source-srcset-novalid.html - cobalt - Git at Google

 <!DOCTYPE html>
 <meta charset=utf-8>
 <title>invalid always-matching-source-media-all-spaces-with-following-source-srcset</title>
 <picture><source srcset=x media=' all '><source srcset=x><img src=x alt></picture>
	<!DOCTYPE html>
	<meta charset=utf-8>
	<title>invalid always-matching-source-media-all-spaces-with-following-source-srcset</title>
	<picture><source srcset=x media=' all '><source srcset=x><img src=x alt></picture>