I can reproduce the issue on Nightly(20150418030216) which includes patch of Bug 1071562. So, Bug 1071562 did not fix this case at all.
Bug 1638318 Comment 2 Edit History
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I can reproduce the issue on Nightly(20150418030216) which includes patch of Bug 1071562. So, Bug 1071562 did not fix this case at all. I think this is not regression. e10s implementation bug.