[get.https.window.html]
expected:
if os == "win": [OK, TIMEOUT]
[BackgroundFetchManager.get() does not require an activated worker]
expected:
if os == "win": [FAIL, TIMEOUT]
FAIL
[Getting non-existing registrations yields `undefined`]
expected:
if os == "win": [FAIL, NOTRUN]
FAIL
[Getting an existing registration has the expected values]
expected:
if os == "win": [FAIL, NOTRUN]
FAIL