Add fully active check in start()

[shaseley]

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Preview | Diff

[shaseley]

@reillyeon can you PTAL? This is follow-up from https://chromium-review.googlesource.com/c/chromium/src/+/4810975.

A couple notes:

1. IIUC this can be used on workers, so this checks that the object is a Window, but the test below does not check that -- probably a bug?
2. The linked wpt is failing on wpt.fyi, but not in chrome with run_web_tests or run_wpt_tests. Running with wpt serve doesn't seem to include the testdriver-vendor.js file, so I'm not sure how to debug this -- do you happen to have any ideas?

[reillyeon]

2. The linked wpt is failing on wpt.fyi, but not in chrome with run_web_tests or run_wpt_tests. Running with wpt serve doesn't seem to include the testdriver-vendor.js file, so I'm not sure how to debug this -- do you happen to have any ideas?

I'm not sure. I haven't tried running tests with wpt serve in a long time.

[reillyeon]

The equivalent worker concept is "active needed worker". You're right that the code below assumes a Document because the Permissions Policy spec does not currently define how it works in workers. In Chromium, since this API is only available in dedicated workers, the permissions policy is simply inherited from the owning document.