Revert of Shows error messages in the inspector when .respondWith() is called with wrong responses.

Revert of Shows error messages in the inspector when .respondWith() is called with wrong responses. (patchset #4 id:100001 of https://codereview.chromium.org/1228233007/)

Reason for revert:
Causes content_browsertests failures: http://build.chromium.org/p/chromium.webkit/builders/Linux%20Tests/builds/45600

Original issue's description:
> Shows error messages in the inspector when .respondWith() is called with wrong responses.
> 
> To let the developer know about the reason of the failure.
> 
> BUG=505784
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=199287

TBR=mkwst@chromium.org,falken@chromium.org,horo@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=505784
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=199298

[yhirano, 2015-07-22 09:47:54]

Created Revert of Shows error messages in the inspector when .respondWith() is
called with wrong responses.

[commit-bot: I haz the power, 2015-07-22 09:48:39]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1252443003/1

[commit-bot: I haz the power, 2015-07-22 09:50:10]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=199298

[horo, 2015-07-24 01:53:47]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/1250363002/ by horo@chromium.org.

The reason for reverting is: Temporarily disabled the falling test
(ServiceWorkerVersionBrowserTest.FetchEvent_respondWithRejection)
https://crrev.com/1254523002

https://codereview.chromium.org/1252503006/ will update the test expectation.
.