Bug 1027534 - [System][Test] Integration test for inline->window activity call chain

https://bugzilla.mozilla.org/show_bug.cgi?id=1027534
Ok,
 I also file a request for js marionette.we should be able to know displayed app
https://bugzilla.mozilla.org/show_bug.cgi?id=1035048
I'll put it in my comment later.