Handle BeforeHttpsRedirect hook to prohibit HTTP->HTTPS redirect

When browsing *.zero.wikipedia.org on a carrier's network who
does not support HTTPS, prevent automatic HTTP->HTTPS redirection.

This patch won't have any affect until after If04c83066c5d4

Bug 65567

Change-Id: Ia8b620282bb01b3d427ff908e43c74bff9fdabda