[WONT COMMIT] ServiceWorker: Move unregister function from WebSWProvider to WebSWRegistration (1/3)

ServiceWorker: Move unregister function from WebSWProvider to WebSWRegistration (1/3)

This series of CLs changes a call sequence of unregister API.

unregister API was originally exposed on ServiceWorkerContainer interface[1],
so that's still processed via WebServiceWorkerProvider like register() and
getRegistration(). But the API is now exposed on ServiceWorkerRegistration
interface[2] and it seems more natural that WebServiceWorkerRegistration
processes it.

[1] https://slightlyoff.github.io/ServiceWorker/spec/service_worker/index.html#service-worker-container
[2] https://slightlyoff.github.io/ServiceWorker/spec/service_worker/index.html#service-worker-registration-obj

CL dependency:
 (1) Blink: THIS PATCH
 (2) Chromium: https://codereview.chromium.org/896533004/
 (3) Blink: https://codereview.chromium.org/896433005/


BUG=452910
TEST=n/a

[nhiroki, 2015-02-03 05:26:52]

nhiroki@chromium.org changed reviewers:
+ kinuko@chromium.org

[nhiroki, 2015-02-03 05:29:18]

Hi kinuko@, can you review this?

My final goal is to support SWRegistration.unregister() on SWGlobalScope. In the
current implementation, unregister() depends on WebSWProvider, but it's not
available on service worker. I think we should make it available at some point
to support ServiceWorkerContainer on WorkerNavigator, but it wouldn't be
necessary for unregister() function as I explained on the CL description.

Thanks!

[kinuko, 2015-02-03 07:51:00]

lgtm

[nhiroki, 2015-02-03 07:52:15]

nhiroki@chromium.org changed reviewers:
+ tkent@chromium.org

[nhiroki, 2015-02-03 07:52:51]

nhiroki@chromium.org changed reviewers:
+ mkwst@chromium.org
- tkent@chromium.org

[nhiroki, 2015-02-03 07:53:17]

+mkwst@, can you review this? Thanks!

[nhiroki, 2015-02-03 13:02:41]

kinuko@ pointed out that there are crashable cases on the 2nd CL, so I decided
to drop this series of CLs and will make new ones to support WebSWProvider on
SWGlobalScope.