ServiceWorker: Change the return value of ServiceWorkerRegistration::unregister to boolean (4/4)

ServiceWorker: Change the return value of ServiceWorkerRegistration::unregister to boolean (4/4)

BUG=390894
TEST=N/A

Committed: https://crrev.com/620f4c6da423d48ec6eab392e08408dbdd18008d
Cr-Commit-Position: refs/heads/master@{#293154}

[shimazu, 2014-08-28 09:49:18]

shimazu@chromium.org changed reviewers:
+ horo@chromium.org, nhiroki@chromium.org

[shimazu, 2014-08-28 09:49:18]

horo@chromium.org: Please review changes in 

nhiroki@chromium.org: Please review changes in

[horo, 2014-08-29 07:37:50]

lgtm

[shimazu, 2014-09-03 14:17:22]

The CQ bit was checked by shimazu@chromium.org

[commit-bot: I haz the power, 2014-09-03 14:18:42]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/shimazu@chromium.org/509283003/20001

[commit-bot: I haz the power, 2014-09-03 16:15:28]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  linux_chromium_chromeos_rel_swarming on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[commit-bot: I haz the power, 2014-09-03 16:52:46]

Committed patchset #2 (id:20001) as b109e380b8e62cc8c165c959e95b53c0a98042f8

[commit-bot: I haz the power, 2014-09-10 03:26:17]

Patchset 2 (id:??) landed as
https://crrev.com/620f4c6da423d48ec6eab392e08408dbdd18008d
Cr-Commit-Position: refs/heads/master@{#293154}