Revert of Apply AllowCrossThreadAccess() in the callers of createCrossThreadTask()

Revert of Apply AllowCrossThreadAccess() in the callers of createCrossThreadTask() (patchset #9 id:160001 of https://codereview.chromium.org/1766143002/ )

Reason for revert:
Speculatively reverting this to see if it fixes a bunch of media tests on Windows that started failing as soon as this was checked in.

Started here:
https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Win7%20%28dbg%29/builds/5640

Original issue's description:
> Apply AllowCrossThreadAccess() in the callers of createCrossThreadTask()
> 
> This CL removes AllowCrossThreadAccess() calls in CrossThreadTask.h and applies
> AllowCrossThreadAccess() at the callers of createCrossThreadAccess().
> 
> All previous uses of createCrossThreadTask() that would require
> AllowCrossThreadAccess() are detected by compile errors
> due to lack of CrossThreadCopier for WeakPtr/pointers because
> https://codereview.chromium.org/1904283004/ removed CrossThreadCopier for
> GCed pointers.
> 
> BUG=597856
> 
> Committed: https://crrev.com/4c6e26cd4be4f511aa6a62e46c37178605fb3714
> Cr-Commit-Position: refs/heads/master@{#393573}

TBR=tzik@chromium.org,haraken@chromium.org,kinuko@chromium.org,yutak@chromium.org,hiroshige@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=597856

[Finnur, 2016-05-17 12:24:38]

Created Revert of Apply AllowCrossThreadAccess() in the callers of
createCrossThreadTask()

[commit-bot: I haz the power, 2016-05-17 12:24:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1986143002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1986143002/1

[commit-bot: I haz the power, 2016-05-17 12:26:24]

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

[commit-bot: I haz the power, 2016-05-17 12:26:26]

Try jobs failed on following builders:
  ios-device on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-device/builds...)
  ios-device-gn on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-device-gn/bui...)
  ios-simulator-gn on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator-gn/...)

[haraken, 2016-05-17 12:38:31]

LGTM to revert

[hiroshige, 2016-05-17 12:40:30]

On 2016/05/17 12:26:26, commit-bot: I haz the power wrote:
> Try jobs failed on following builders:
>   ios-device on tryserver.chromium.mac (JOB_FAILED,
>
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-device/builds...)
>   ios-device-gn on tryserver.chromium.mac (JOB_FAILED,
>
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-device-gn/bui...)
>   ios-simulator-gn on tryserver.chromium.mac (JOB_FAILED,
>
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator-gn/...)

Several CLs depends on this CL and at least two (and probably more) CLs should
be reverted together.

[hiroshige, 2016-05-17 12:44:57]

On 2016/05/17 12:40:30, hiroshige wrote:
> On 2016/05/17 12:26:26, commit-bot: I haz the power wrote:
> > Try jobs failed on following builders:
> >   ios-device on tryserver.chromium.mac (JOB_FAILED,
> >
>
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-device/builds...)
> >   ios-device-gn on tryserver.chromium.mac (JOB_FAILED,
> >
>
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-device-gn/bui...)
> >   ios-simulator-gn on tryserver.chromium.mac (JOB_FAILED,
> >
>
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator-gn/...)
> 
> Several CLs depends on this CL and at least two (and probably more) CLs should
> be reverted together.

According to
https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Win7%20%28dbg%...,
the change lists contains some rebaselines for some (most?) failed tests (e.g.
r393582).
Perhaps rebaseline error?

FYI at least the following CLs depends on this CL and thus should be reverted
first.
https://codereview.chromium.org/1905343002/
https://codereview.chromium.org/1914453002/

[Finnur, 2016-05-17 13:20:51]

> According to
>
https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Win7%20%28dbg%...,
> the change lists contains some rebaselines for some (most?) failed tests (e.g.
> r393582).
> Perhaps rebaseline error?

Hmm, good catch. I missed that. I'll mark the tests instead.

> 
> FYI at least the following CLs depends on this CL and thus should be reverted
> first.
> https://codereview.chromium.org/1905343002/
> https://codereview.chromium.org/1914453002/

I don't know. I don't have much of an appetite for multi-level speculative
reverts (not even sure your CL is to blame). :)

[hiroshige, 2016-05-17 13:54:49]

On 2016/05/17 13:20:51, Finnur wrote:
> > According to
> >
>
https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Win7%20%28dbg%...,
> > the change lists contains some rebaselines for some (most?) failed tests
(e.g.
> > r393582).
> > Perhaps rebaseline error?
> 
> Hmm, good catch. I missed that. I'll mark the tests instead.
> 
> > 
> > FYI at least the following CLs depends on this CL and thus should be
reverted
> > first.
> > https://codereview.chromium.org/1905343002/
> > https://codereview.chromium.org/1914453002/
> 
> I don't know. I don't have much of an appetite for multi-level speculative
> reverts (not even sure your CL is to blame). :)

Filed https://crbug.com/612442.