ServiceWorker: Rename OnRegistrationStored -> OnRegistrationCompleted.

For historical reasons, OnRegistrationStored() is called when the
promise returned by ServiceWorkerContainer.register() is resolved, which
happens before the registration is written to disk. This means
OnRegistrationStored() implementations cannot assume that
ServiceWorkerContextCore will be able to retrieve the registration.

This CL renames the method to a more appropriate name. A follow-up CL
will add an OnRegistrationStored() method, which will be called when the
registration is written to the database.

TBR=benwells

Bug: 729800
Change-Id: If273b3008ff55e4d5cd8f5be9e0e6090da2e5390
Reviewed-on: https://chromium-review.googlesource.com/1039083
Commit-Queue: Victor Costan <pwnall@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Matt Falkenhagen <falken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#555550}
12 files changed