Make registration.update() no longer force bypassing the HTTP cache

Make registration.update() no longer force bypassing the HTTP cache

As per the last f2f and the follow-up discussion,
ServiceWorkerRegistration.update() should not always bypass the HTTP cache but
bypass it only when 24 hours have passed since the last update check. So, this
patch involves a change in the behavior of ServiceWorkerRegistration.update().

Spec: https://slightlyoff.github.io/ServiceWorker/spec/service_worker/index.html#service-worker-registration-update
Spec discussion: https://github.com/slightlyoff/ServiceWorker/issues/514#issuecomment-130664373

This CL merged two CLs that were created and under review before Blink and
Chromium repos were merged:
 1. Blink: https://codereview.chromium.org/1332303002/
 2. Chromium: https://codereview.chromium.org/1339623002/

BUG=530540
Committed: https://crrev.com/395e4a2444b1e74c753cde3eb4de342e57bb2915
Cr-Commit-Position: refs/heads/master@{#352232}

[jungkees, 2015-10-02 13:52:18]

jungkee.song@samsung.com changed reviewers:
+ falken@chromium.org, jinho.bang@samsung.com, kinuko@chromium.org,
l.gombos@samsung.com, michaeln@chromium.org, nhiroki@chromium.org

[jungkees, 2015-10-02 13:56:07]

I made this new patch to land https://codereview.chromium.org/1332303002 and
https://codereview.chromium.org/1339623002 as a single CL. PTAL

[falken, 2015-10-02 14:04:02]

lgtm

[jungkees, 2015-10-03 02:18:33]

The CQ bit was checked by jungkee.song@samsung.com

[commit-bot: I haz the power, 2015-10-03 02:18:54]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1380323002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1380323002/1

[commit-bot: I haz the power, 2015-10-03 03:36:37]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-03 03:37:42]

Patchset 1 (id:??) landed as
https://crrev.com/395e4a2444b1e74c753cde3eb4de342e57bb2915
Cr-Commit-Position: refs/heads/master@{#352232}