This is also in Radar as 4005252 - go to ebay.com - search for something - scroll down at the search results page - click on an item - go back after the page for that item has loaded result: you're back at the search results page, but the scroll position is not restored This is makes searching for things at ebay very difficult. Firefox does not have this problem.
I stumbled onto a way to get the same behavior when I had some breakpoints set in gdb, at nytimes.com. I only rarely could make it happen at ebay, but it seems like a good chance that it is the same bug. The flakey behavior is consistent with my analysis of it being a race condition.
Created attachment 3010 [details] proposed patch - also fixes 4051
Created attachment 3013 [details] proposed patch - also fixes 4061
Comment on attachment 3013 [details] proposed patch - also fixes 4061 So this doesn't fix 4051 after all? Bummer. Still, nice fix.
I checked this in.
Comment on attachment 3010 [details] proposed patch - also fixes 4051 Taking off review flag to make this stop showing up in the needs review query.