[M53] service worker: Wait for inflight requests before activating

[M53] service worker: Wait for inflight requests before activating

This patch makes changes as per discussion at
https://github.com/slightlyoff/ServiceWorker/issues/916

Namely,
* The waiting worker gets promoted to active once there are no
controllees and the incumbent worker has no in-flight events
(fetch/sync/push/message etc).
* skipWaiting bypasses the no controllees requirement, but we
still wait until there are no in-flight events.
* As usual, incoming fetch/sync/push events always go to the
active worker.

BUG=616331
Review-Url: https://codereview.chromium.org/2119143002
Cr-Commit-Position: refs/heads/master@{#405628}
(cherry picked from commit 6c95b0ff8f694cda918e38c96387e5445713fc8e)

Committed: https://chromium.googlesource.com/chromium/src/+/2d740ca87cb68f2fbc558a34eb1f1e8328dd6470

[falken, 2016-07-21 05:58:49]

Description was changed from

==========
[M53] service worker: Wait for inflight requests before activating

This patch makes changes as per discussion at
https://github.com/slightlyoff/ServiceWorker/issues/916

Namely,
* The waiting worker gets promoted to active once there are no
controllees and the incumbent worker has no in-flight events
(fetch/sync/push/message etc).
* skipWaiting bypasses the no controllees requirement, but we
still wait until there are no in-flight events.
* As usual, incoming fetch/sync/push events always go to the
active worker.

BUG=616331

Review-Url: https://codereview.chromium.org/2119143002
Cr-Commit-Position: refs/heads/master@{#405628}
(cherry picked from commit 6c95b0ff8f694cda918e38c96387e5445713fc8e)
==========

to

==========
[M53] service worker: Wait for inflight requests before activating

This patch makes changes as per discussion at
https://github.com/slightlyoff/ServiceWorker/issues/916

Namely,
* The waiting worker gets promoted to active once there are no
controllees and the incumbent worker has no in-flight events
(fetch/sync/push/message etc).
* skipWaiting bypasses the no controllees requirement, but we
still wait until there are no in-flight events.
* As usual, incoming fetch/sync/push events always go to the
active worker.

BUG=616331

Review-Url: https://codereview.chromium.org/2119143002
Cr-Commit-Position: refs/heads/master@{#405628}
(cherry picked from commit 6c95b0ff8f694cda918e38c96387e5445713fc8e)

Committed:
https://chromium.googlesource.com/chromium/src/+/2d740ca87cb68f2fbc558a34eb1f...
==========

[falken, 2016-07-21 05:58:51]

Committed patchset #1 (id:1) manually as
2d740ca87cb68f2fbc558a34eb1f1e8328dd6470.