Revert of Prevent calling didReceiveData()/didFinishLoading() after didFailAccessControlCheck()

Revert of Prevent calling didReceiveData()/didFinishLoading() after didFailAccessControlCheck() (patchset #6 id:100001 of https://codereview.chromium.org/891263002/)

Reason for revert:
Broke some nacl browser_tests: http://test-results.appspot.com/dashboards/flakiness_dashboard.html#testType=browser_tests&tests=NaClBrowserTestStatic.CORSNoCookie%2CNaClBrowserTestStatic.CrossOriginFail%2CPnaclHeaderTest.TestHasPnaclHeader

Original issue's description:
> Prevent calling didReceiveData()/didFinishLoading() after didFailAccessControlCheck()
> 
> In some cases DocumentThreadableLoader calls m_client->didReceiveData() or
> didFinishLoading() after m_client->didFailAccessControlCheck().
> WorkerLoaderClientBridgeSyncHelper assumes no calls are made to
> ThreadableLoaderClient after didFailAccessControlCheck(), and this mismatch
> results in a race condition.
> 
> This CL fixes this by omitting calls to didReceiveData()/didFinishLoading()
> after didFailAccessControlCheck() using |m_accessControlCheckFailed| flag.
> handlePreflightFailure() is called instead of didFailAccessControlCheck() to
> ensure |m_accessControlCheckFailed| and |m_actualRequest| are properly managed.
> 
> This CL also makes WorkerLoaderClientBridgeSyncHelper to ASSERT/ignore did*()
> calls after any of didFail*() or didFinishLoading() is called.
> This explicitly states the assumptions of WorkerLoaderClientBridgeSyncHelper,
> and prevents possible race conditions as defensive programming.
> 
> BUG=421627
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=189418

TBR=tyoshino@chromium.org,kinuko@chromium.org,mkwst@chromium.org,hiroshige@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=421627
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=189439

[Nate Chapin, 2015-02-03 22:05:00]

Created Revert of Prevent calling didReceiveData()/didFinishLoading() after
didFailAccessControlCheck()

[commit-bot: I haz the power, 2015-02-03 22:06:14]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/902453002/1

[commit-bot: I haz the power, 2015-02-03 22:06:55]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=189439

[Mike West, 2015-02-04 05:24:43]

LGTM, thanks for reverting.