Right now there's some duplicated code with the focus manager and the
DOMWindowFocus event.
Android didn't handle the new framefocusrequested event, so the test-cases in
bug 416771 still didn't work there.
I think using the focus manager codepath everywhere is preferable. I confirmed
manually that the stuff that sent DOMWindowFocus events still works as expected
with this patch (i.e., switching to the right tab when you click on a
notification, etc.).
This fixes it so that it works in Fennec, and it sends the focus events right in
GeckoView Example (i.e., we get here[1] properly).
The snippet that Snorp provided on IRC to implement the "bring activity to
front" stuff (`startActivity(getIntent())`) didn't actually work for me, but I
confirmed that the right message is sent when the focus is requested, and that
we get there.
[1]: https://searchfox.org/mozilla-central/rev/952521e6164ddffa3f34bc8cfa5a81afc5b859c4/mobile/android/geckoview_example/src/main/java/org/mozilla/geckoview_example/GeckoViewActivity.java#503
Depends on D32353
Differential Revision: https://phabricator.services.mozilla.com/D32354
b56d5ba7d7