CacheStorage: Pass an error object allocated on heap to WebCallbacks::onError (4)

CacheStorage: Pass an error object allocated on heap to WebCallbacks::onError (4)

This is a preliminary patch to simplify memory management in
CallbackPromiseAdapter. See (1) for details.

(1) Chromium: https://codereview.chromium.org/1152003008
(2) Blink: https://codereview.chromium.org/1155573003
(3) Chromium: https://codereview.chromium.org/1150333003
(4) Blink: THIS PATCH

BUG=494884
TEST=n/a

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=197360

[nhiroki, 2015-06-17 08:35:54]

Patchset #1 (id:1) has been deleted

[jkarlin, 2015-06-17 12:14:36]

jkarlin@chromium.org changed reviewers:
+ jkarlin@chromium.org

[jkarlin, 2015-06-17 12:14:36]

lgtm

[nhiroki, 2015-06-18 01:05:23]

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

[nhiroki, 2015-06-18 01:05:24]

+tkent@, ptal, thanks!

[tkent, 2015-06-18 01:06:05]

lgtm

[nhiroki, 2015-06-18 13:56:03]

The CQ bit was checked by nhiroki@chromium.org

[nhiroki, 2015-06-18 13:56:04]

The patchset sent to the CQ was uploaded after l-g-t-m from jkarlin@chromium.org
Link to the patchset: https://codereview.chromium.org/1150413004/#ps40001
(title: "rebase")

[commit-bot: I haz the power, 2015-06-18 13:56:14]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1150413004/40001

[commit-bot: I haz the power, 2015-06-18 15:19:35]

Committed patchset #2 (id:40001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=197360