https://crrev.com/f68c52f414b7b785720faf53458df2517e921c9e regressed the is_offline_preview() logic by moving the time the variable is set to DidFinishNavigation. The only consumer of is_offline_preview() is in a different DidFinishNavigation that occurs before the OfflinePreviewsTabHelper::DidFinishNavigation
Comment 1 by ryansturm@chromium.org
, Oct 12 2016