[ServiceWorker] clarify Request.isReload for sub-resources (#827)

Current the spec text for .isReload is a bit vague.  Step 18.4 of Handle Fetch says:

> Let the isReload attribute of e be initialized to true if request's client is a window client and the event was dispatched with the user's intention for the page reload, and false otherwise.

Obviously a lot of hand waving in "user's intention" here.

Both chrome and firefox only set this for the top level navigation that is triggered from a refresh.  All sub-resources get .isReload=false.

Over in this chrome issue devs are asking that to change:

  https://code.google.com/p/chromium/issues/detail?id=579866

But its unclear to me what this means for subresources.  I see some possibilities:

1) All sub-resources loaded synchronously during reload get .isReload = true
2) Sub-resources loaded sync and async before load event get .isReload = true
3) Sub-resources from a reloaded document always get .isReload = true even if they are async requested an hour later, etc.

I think (1) or (2) make the most sense for developers.  Thoughts?

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Reply to this email directly or view it on GitHub:
https://github.com/slightlyoff/ServiceWorker/issues/827