8713fa0dfc
We had some protection in https://searchfox.org/mozilla-central/rev/2fc2ccf960c2f7c419262ac7215715c5235948db/dom/base/nsGlobalWindowOuter.cpp#4259-4265, but it isn't enough, it is still possible that fullscreen state get confused if there are multiple request happens at a short time. This patch tries to improve how we handle multiple request, we don't need to track each request, but need to ensure widget matches with the latest fullscreen state specified. Differential Revision: https://phabricator.services.mozilla.com/D163311