Draft: fixup! Bug 27476: Implement about:torconnect captive portal within Tor Browser

This change updates when OnionAliasStore and its HttpsEverywhereControl object are initialized. The HttpsEverywhereControl now updates for all subscribed channels on init. When we switch from offline to online, we trigger this code path. If we are not starting in offline (as when using the legacy tor launcher) then everything proceeds as before. In fact, its a bit better because now all of the HTTPS Everywhere Channels are updated on launch, rather than waiting for the time interval.