Revert of Use TaskScheduler instead of WorkerPool in client_cert_store_chromeos.cc.

Revert of Use TaskScheduler instead of WorkerPool in client_cert_store_chromeos.cc. (patchset #7 id:120001 of https://codereview.chromium.org/2533473002/ )

Reason for revert:
Using TaskScheduler with NSS is not safe until TaskScheduler supports dynamically growing its thread pool.

Original issue's description:
> Use TaskScheduler instead of WorkerPool in client_cert_store_chromeos.cc.
> 
> This CL replaces base::WorkerPool::PostTask() with
> base::PostTaskWithTraits(). The following traits are used:
> 
> Priority: Inherited (default)
>   The priority is inherited from the calling context (i.e. TaskTraits
>   are initialized with the priority of the current task).
> 
> Shutdown behavior: CONTINUE_ON_SHUTDOWN
>   Tasks posted with this mode which have not started executing before
>   shutdown is initiated will never run. Tasks with this mode running at
>   shutdown will be ignored (the worker will not be joined).
> 
> With File IO:
>   The task waits on synchronous file IO operations.
> 
> With Wait:
>   The task waits on things other than synchronous file IO
>   operations (e.g. WaitableEvent, ConditionVariable, join a thread,
>   join a process, blocking system call that doesn't involve
>   interactions with the file system).
> 
> BUG=659191
> 
> Committed: https://crrev.com/14589e9ca09b5cf03be779b0c1158cc5388def05
> Cr-Commit-Position: refs/heads/master@{#436087}

TBR=gab@chromium.org,mattm@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=659191
Review-Url: https://codereview.chromium.org/2720143003
Cr-Commit-Position: refs/heads/master@{#453460}
Committed: https://chromium.googlesource.com/chromium/src/+/f945b5f336da1fd246e2a0a24a5633547034287b

[fdoray, 2017-02-28 01:26:06]

The CQ bit was checked by fdoray@chromium.org

[fdoray, 2017-02-28 01:26:07]

Created Revert of Use TaskScheduler instead of WorkerPool in
client_cert_store_chromeos.cc.

[commit-bot: I haz the power, 2017-02-28 01:26:41]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-02-28 01:29:38]

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

[fdoray, 2017-02-28 01:30:34]

The CQ bit was checked by fdoray@chromium.org

[fdoray, 2017-02-28 01:30:48]

The CQ bit was unchecked by fdoray@chromium.org

[fdoray, 2017-02-28 01:32:28]

The CQ bit was checked by fdoray@chromium.org

[commit-bot: I haz the power, 2017-02-28 01:33:24]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[gab, 2017-02-28 01:42:40]

Also add
https://groups.google.com/a/chromium.org/d/topic/net-dev/SubA-WOEB18/discussion
to revert reason.

lgtm w/ comments (deferring to mattm for resolution)

https://codereview.chromium.org/2720143003/diff/90001/chrome/browser/chromeos...
File chrome/browser/chromeos/net/client_cert_store_chromeos.cc (right):

https://codereview.chromium.org/2720143003/diff/90001/chrome/browser/chromeos...
chrome/browser/chromeos/net/client_cert_store_chromeos.cc:84: if
(base::WorkerPool::PostTaskAndReply(
Probably don't need to bring back handling PostTask returning false?

https://codereview.chromium.org/2720143003/diff/90001/chrome/browser/chromeos...
File chrome/browser/chromeos/net/client_cert_store_chromeos_unittest.cc (right):

https://codereview.chromium.org/2720143003/diff/90001/chrome/browser/chromeos...
chrome/browser/chromeos/net/client_cert_store_chromeos_unittest.cc:91:
std::unique_ptr<base::MessageLoop> message_loop_;
Can this just be a base::MessageLoopForIO member? Or even just a
base::MessageLoop (seems you didn't need an IO loop in reverted CL?)

[commit-bot: I haz the power, 2017-02-28 02:19:42]

CQ is committing da patch.

Bot data: {"patchset_id": 90001, "attempt_start_ts": 1488245548707330,
"parent_rev": "a17c6984f4b9369e8ce061018d31e4ecf64f7fdf", "commit_rev":
"f945b5f336da1fd246e2a0a24a5633547034287b"}

[commit-bot: I haz the power, 2017-02-28 02:20:22]

Description was changed from

==========
Revert of Use TaskScheduler instead of WorkerPool in
client_cert_store_chromeos.cc. (patchset #7 id:120001 of
https://codereview.chromium.org/2533473002/ )

Reason for revert:
Using TaskScheduler with NSS is not safe until TaskScheduler supports
dynamically growing its thread pool.

Original issue's description:
> Use TaskScheduler instead of WorkerPool in client_cert_store_chromeos.cc.
> 
> This CL replaces base::WorkerPool::PostTask() with
> base::PostTaskWithTraits(). The following traits are used:
> 
> Priority: Inherited (default)
>   The priority is inherited from the calling context (i.e. TaskTraits
>   are initialized with the priority of the current task).
> 
> Shutdown behavior: CONTINUE_ON_SHUTDOWN
>   Tasks posted with this mode which have not started executing before
>   shutdown is initiated will never run. Tasks with this mode running at
>   shutdown will be ignored (the worker will not be joined).
> 
> With File IO:
>   The task waits on synchronous file IO operations.
> 
> With Wait:
>   The task waits on things other than synchronous file IO
>   operations (e.g. WaitableEvent, ConditionVariable, join a thread,
>   join a process, blocking system call that doesn't involve
>   interactions with the file system).
> 
> BUG=659191
> 
> Committed: https://crrev.com/14589e9ca09b5cf03be779b0c1158cc5388def05
> Cr-Commit-Position: refs/heads/master@{#436087}

TBR=gab@chromium.org,mattm@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=659191
==========

to

==========
Revert of Use TaskScheduler instead of WorkerPool in
client_cert_store_chromeos.cc. (patchset #7 id:120001 of
https://codereview.chromium.org/2533473002/ )

Reason for revert:
Using TaskScheduler with NSS is not safe until TaskScheduler supports
dynamically growing its thread pool.

Original issue's description:
> Use TaskScheduler instead of WorkerPool in client_cert_store_chromeos.cc.
> 
> This CL replaces base::WorkerPool::PostTask() with
> base::PostTaskWithTraits(). The following traits are used:
> 
> Priority: Inherited (default)
>   The priority is inherited from the calling context (i.e. TaskTraits
>   are initialized with the priority of the current task).
> 
> Shutdown behavior: CONTINUE_ON_SHUTDOWN
>   Tasks posted with this mode which have not started executing before
>   shutdown is initiated will never run. Tasks with this mode running at
>   shutdown will be ignored (the worker will not be joined).
> 
> With File IO:
>   The task waits on synchronous file IO operations.
> 
> With Wait:
>   The task waits on things other than synchronous file IO
>   operations (e.g. WaitableEvent, ConditionVariable, join a thread,
>   join a process, blocking system call that doesn't involve
>   interactions with the file system).
> 
> BUG=659191
> 
> Committed: https://crrev.com/14589e9ca09b5cf03be779b0c1158cc5388def05
> Cr-Commit-Position: refs/heads/master@{#436087}

TBR=gab@chromium.org,mattm@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=659191

Review-Url: https://codereview.chromium.org/2720143003
Cr-Commit-Position: refs/heads/master@{#453460}
Committed:
https://chromium.googlesource.com/chromium/src/+/f945b5f336da1fd246e2a0a24a56...
==========

[commit-bot: I haz the power, 2017-02-28 02:20:23]

Committed patchset #3 (id:90001) as
https://chromium.googlesource.com/chromium/src/+/f945b5f336da1fd246e2a0a24a56...