When receiving DefaultBrowserClosing or suspend, the browser is going into a state from which it can be terminated without notification. So we should send some sort of a mozilla notification so services know this is happening. Also on suspend, we have the ability to delay the suspend for a period of time for things like active downloads. We'll need to figure out a way to let services communicate that they want a delay. (Or maybe we poll certain services like the download manager for state.)

From the ms doc: Close gesture Users may choose to close a Metro style enabled desktop browser via operating system features such as the keyboard combination ALT+F4 or by using the close gesture. Users invoke the close gesture by “dragging” a representation of the window from the top of the app to the bottom of the screen. When the Metro style enabled desktop browser is active (not suspended, not in the background), painting via ICoreWindow, it will be sent a registered window message with the string “DefaultBrowserClosing” as it moves off screen during window close. The browser should use this message as a signal to prepare for termination after suspension is complete.

I'm not sure if elm is in a good state right now so I don't want to update yet :) Here's the code for this task though. - Hooked up events. - Registered for the events at the same places that we sleep/resume - Fixed download manager so it works with these events in fennec (some missing prefs were needed) - Added event notification for the registered message DefaultBrowserClosing, and verified it is indeed sent to us.

I made a slight change to this - xpcom fires a number of shutdown events that all of our components listen for, so rather than fire a new observer event and respond to that in the front by calling quit, just call quit directly. I think this will be better since the stack should be less wound up when we make the call. https://hg.mozilla.org/projects/elm/rev/0236392b4e80

Sounds good, thanks

All differences are in elm->m-c merge migration locations, so resolving this.