Error when saving edits to Template pages

[The-Foilist]

This error arose after upgrading from MediaWiki version 1.36 to version 1.37.1, and after I applied my fix #51 . It occurs whenever I try to save an edit to any page in the Template namespace when PortableInfobox is installed. Here's the trace:

Error: Class 'RevisionRecord' not found

Backtrace:

from /var/www/w/extensions/PortableInfobox/includes/services/Helpers/PortableInfoboxParsingHelper.php(76)
#0 /var/www/w/extensions/PortableInfobox/includes/services/Helpers/PortableInfoboxParsingHelper.php(27): PortableInfobox\Helpers\PortableInfoboxParsingHelper->fetchArticleContent()
#1 /var/www/w/extensions/PortableInfobox/includes/services/PortableInfoboxDataService.php(199): PortableInfobox\Helpers\PortableInfoboxParsingHelper->parseIncludeonlyInfoboxes()
#2 /var/www/w/extensions/PortableInfobox/includes/PortableInfobox.hooks.php(45): PortableInfoboxDataService->reparseArticle()
#3 /var/www/w/includes/HookContainer/HookContainer.php(338): PortableInfoboxHooks::onPageContentSave()
#4 /var/www/w/includes/HookContainer/HookContainer.php(137): MediaWiki\HookContainer\HookContainer->callLegacyHook()
#5 /var/www/w/includes/HookContainer/HookRunner.php(2714): MediaWiki\HookContainer\HookContainer->run()
#6 /var/www/w/includes/Storage/PageUpdater.php(807): MediaWiki\HookContainer\HookRunner->onPageContentSave()
#7 /var/www/w/includes/page/WikiPage.php(1994): MediaWiki\Storage\PageUpdater->saveRevision()
#8 /var/www/w/includes/EditPage.php(2351): WikiPage->doUserEditContent()
#9 /var/www/w/includes/EditPage.php(1687): EditPage->internalAttemptSave()
#10 /var/www/w/includes/EditPage.php(665): EditPage->attemptSave()
#11 /var/www/w/includes/actions/EditAction.php(71): EditPage->edit()
#12 /var/www/w/includes/actions/SubmitAction.php(38): EditAction->show()
#13 /var/www/w/includes/MediaWiki.php(543): SubmitAction->show()
#14 /var/www/w/includes/MediaWiki.php(320): MediaWiki->performAction()
#15 /var/www/w/includes/MediaWiki.php(930): MediaWiki->performRequest()
#16 /var/www/w/includes/MediaWiki.php(564): MediaWiki->main()
#17 /var/www/w/index.php(53): MediaWiki->run()
#18 /var/www/w/index.php(46): wfIndexMain()
#19 {main}

It looks like the Revision class was removed in MW version 1.37. According to this migration guide on MediaWiki.org, Revision::FOR_PUBLIC should be replaced with RevisionRecord::FOR_PUBLIC in this file.