And has been for a long time (since at least r90501) :( http://test-results.appspot.com/dashboards/flakiness_dashboard.html#showExpectations=true&tests=http%2Ftests%2Fnavigation%2Flockedhistory-iframe.html
Duping against larger bug about frame navigation tests being flaky. *** This bug has been marked as a duplicate of bug 112980 ***