LookalikeUrlNavigationObserverBrowserTest.Idn_SiteEngagement_Match/0
LookalikeUrlNavigationObserverBrowserTest.Idn_SiteEngagement_Match/1

are timing out a lot on all platforms :

https://test-results.appspot.com/dashboards/flakiness_dashboard.html#tests=LookalikeUrlNavigationObserverBrowserTest.Idn_SiteEngagement_Match%2F1

Looks like it's looping over kSiteEngagementTestCases. Can those instead be split in different tests?