Bug 1246956 - Stealing of URL cross-domain using perfomance.getEntries() after restore previous session

PoC tested on Mac OS X El Capitan 10.11 on Mozilla Firefox 44
TestCase : http://www.alternativ-testing.fr/Research/Mozilla/9KH65-cross%20origin%20URLs%20Bypass/xframe%20Cross%20Origin%20URLs%20Bypass.html