Reland of Skip the Service Worker CORS fallback for same origin requests. [2/2 chromium]

Reland of Skip the Service Worker CORS fallback for same origin requests. [2/2 chromium] (patchset #1 id:1 of https://codereview.chromium.org/1258893004/ )

Reason for revert:
LayoutTest failure was fixed by https://codereview.chromium.org/1274973002/

Original issue's description:
> Revert of Skip the Service Worker CORS fallback for same origin requests. [2/2 chromium] (patchset #1 id:40001 of https://codereview.chromium.org/1242953007/)
>
> Reason for revert:
> This broke http/tests/serviceworker/fetch-request-fallback.html, causing failures on 3 bots and timeouts on 18 bots.
>
> See http://test-results.appspot.com/dashboards/flakiness_dashboard.html#tests=http%2Ftests%2Fserviceworker%2Ffetch-request-fallback.html&testType=layout-tests
>
> Original issue's description:
> > Skip the Service Worker CORS fallback for same origin requests. [2/2 chromium]
> >
> > We are sending CORS fallback response from the browser process to the page's renderer process, when the ServiceWorker doesn't handle the CORS fetch request.
> > But when the request URL's origin is same as the page's security origin, we can skip the fallback and send the request from the browser process.
> >
> > This change will improve the delay of the CORS fallback for same origin requests, especially when the renderer main thread is busy.
> >
> > 1/2 blink: https://codereview.chromium.org/1243353002/
> > 2/2 chromium: this cl.
> >
> > BUG=512764
> >
> > Committed: https://crrev.com/97b13409b0c601f21f048744fa8e31852b476337
> > Cr-Commit-Position: refs/heads/master@{#341482}
>
> TBR=falken@chromium.org,tyoshino@chromium.org,horo@chromium.org
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=512764
>
> Committed: https://crrev.com/ac2794675706a635dd3e54245c27f64411927a6c
> Cr-Commit-Position: refs/heads/master@{#341499}

TBR=falken@chromium.org,tyoshino@chromium.org,johnme@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
BUG=512764
Committed: https://crrev.com/1c22502f89533202d0edffa4c69847edcc82f1c0
Cr-Commit-Position: refs/heads/master@{#342600}

[horo, 2015-08-10 07:39:50]

Created Reland of Skip the Service Worker CORS fallback for same origin
requests. [2/2 chromium]

[horo, 2015-08-10 08:16:51]

The CQ bit was checked by horo@chromium.org

[commit-bot: I haz the power, 2015-08-10 08:16:59]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1282193002/30002
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1282193002/30002

[commit-bot: I haz the power, 2015-08-10 09:09:52]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-08-10 09:09:53]

Try jobs failed on following builders:
  win_chromium_x64_rel_ng on tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_x64_...)

[horo, 2015-08-10 09:36:27]

The CQ bit was checked by horo@chromium.org

[commit-bot: I haz the power, 2015-08-10 09:36:35]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1282193002/30002
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1282193002/30002

[commit-bot: I haz the power, 2015-08-10 10:09:00]

Committed patchset #2 (id:30002)

[commit-bot: I haz the power, 2015-08-10 10:09:35]

Patchset 2 (id:??) landed as
https://crrev.com/1c22502f89533202d0edffa4c69847edcc82f1c0
Cr-Commit-Position: refs/heads/master@{#342600}