Split Closure part of TestPendingTask out of the struct

Split Closure part of TestPendingTask out of the struct

This CL extracts base::Closure out of TestPendingTask, and convert it to
base::OnceClosure.

OnceClosure is a move-only and call-once variant of Callback, that we
want to replace Closure with it. Since OnceClosure is noncopyable and
needs to be non const to run. However in general, once we put an object
into std::priority_queue or std::set, we can't take it from the container
without const qualifier.
To avoid it, this CL splits TestPendingTask into TestPendingTaskInfo and
OnceClosure, so that we can store and take the non-const OnceClosure object
using TestPendingTaskInfo as the key.

CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel

[tzik, 2017-01-11 09:50:27]

Description was changed from

==========
Split Closure part of TestPendingTask out of the struct

BUG=
==========

to

==========
Split Closure part of TestPendingTask out of the struct

BUG=
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
==========

[tzik, 2017-01-11 09:50:32]

The CQ bit was checked by tzik@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-11 09:50:48]

Dry run: 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, 2017-01-11 10:15:44]

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

[commit-bot: I haz the power, 2017-01-11 10:15:45]

Dry run: Try jobs failed on following builders:
  linux_chromium_chromeos_ozone_rel_ng on master.tryserver.chromium.linux
(JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[tzik, 2017-01-11 11:34:58]

The CQ bit was checked by tzik@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-11 11:35:14]

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

[tzik, 2017-01-11 12:01:30]

The CQ bit was checked by tzik@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-11 12:02:43]

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

[tzik, 2017-01-11 12:46:18]

The CQ bit was checked by tzik@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-11 12:46:38]

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

[tzik, 2017-01-11 13:02:55]

The CQ bit was checked by tzik@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-11 13:03:05]

Dry run: 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, 2017-01-11 13:47:06]

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

[commit-bot: I haz the power, 2017-01-11 13:47:07]

Dry run: Try jobs failed on following builders:
  win_clang on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_clang/builds/...)

[tzik, 2017-01-12 03:55:09]

The CQ bit was checked by tzik@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-12 03:55:29]

Dry run: 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, 2017-01-12 05:04:20]

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

[commit-bot: I haz the power, 2017-01-12 05:04:25]

Dry run: Try jobs failed on following builders:
  win_clang on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_clang/builds/...)

[tzik, 2017-01-12 06:56:38]

The CQ bit was checked by tzik@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-12 06:56:51]

Dry run: 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, 2017-01-12 09:05:42]

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

[commit-bot: I haz the power, 2017-01-12 09:05:43]

Dry run: Try jobs failed on following builders:
  mac_chromium_rel_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[tzik, 2017-01-12 13:45:30]

The CQ bit was checked by tzik@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-12 13:45:41]

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

[tzik, 2017-01-12 14:05:48]

Description was changed from

==========
Split Closure part of TestPendingTask out of the struct

BUG=
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
==========

to

==========
Split Closure part of TestPendingTask out of the struct

This CL extracts base::Closure out of TestPendingTask, and convert it to
base::OnceClosure.

OnceClosure is a move-only and call-once variant of Callback, that we
want to replace Closure with it. Since OnceClosure is noncopyable and
needs to be non const to run. However in general, once we put an object
into std::priority_queue or std::set, we can't take it from the container
without const qualifier.
To avoid it, this CL splits TestPendingTask into TestPendingTaskInfo and
OnceClosure, so that we can store and take the non-const OnceClosure object
using TestPendingTaskInfo as the key.

CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
==========

[commit-bot: I haz the power, 2017-01-12 15:38:09]

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

[commit-bot: I haz the power, 2017-01-12 15:38:12]

Dry run: This issue passed the CQ dry run.

[tzik, 2017-01-12 16:07:20]

tzik@chromium.org changed reviewers:
+ dcheng@chromium.org

[tzik, 2017-01-12 16:07:32]

tzik@chromium.org changed reviewers:
- dcheng@chromium.org

[tzik, 2017-01-12 23:16:46]

tzik@chromium.org changed reviewers:
+ dcheng@chromium.org

[tzik, 2017-01-12 23:16:47]

PTAL

[tzik, 2017-01-16 13:51:43]

The CQ bit was checked by tzik@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-16 13:51:53]

Dry run: 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, 2017-01-16 15:39:11]

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

[commit-bot: I haz the power, 2017-01-16 15:39:12]

Dry run: This issue passed the CQ dry run.

[dcheng, 2017-01-17 22:18:18]

On 2017/01/12 23:16:47, tzik wrote:
> PTAL

How urgent is this CL? I'd rather not land CLs like this. I'm hoping we can work
on moving Chrome over to containers where we don't have to actively fight the
implementation to make it work correctly.

[tzik, 2017-01-18 13:32:12]

On 2017/01/17 22:18:18, dcheng wrote:
> On 2017/01/12 23:16:47, tzik wrote:
> > PTAL
> 
> How urgent is this CL? I'd rather not land CLs like this. I'm hoping we can
work
> on moving Chrome over to containers where we don't have to actively fight the
> implementation to make it work correctly.

It's not in the time pressure, but this blocks base::TaskRunner migration from
Callback to OnceCallback.
This CL is essentially to avoid the constness of the value of std::set and
std::priority_queue. So, another option is using const_cast. That looks less
clean to me, though it'll require smaller change.