Use OnceCallback on Mojo interfaces in //content

Use OnceCallback on Mojo interfaces in //content

This CL flips `use_once_calback` flag on the Mojo code generator, and
fixes all compile errors after it. After this CL, Mojo interfaces in
//content starts using base::OnceCallback instead of base::Callback
on its return value handling.

The migration recipe was:
 - Convert pass-by-ref callback objects to pass-by-value.
 - Use std::move() to forward it to other consumer, or to invoke it
   with Callback::Run().
 - Handle wherever copies are required manually.
 - Check if the conversion doesn't change the semantics. As the transfer
   and invocation clobber the callback object, care about use-after-move.
   It's considered safe to consume almost scoped-out callback.

BUG=714018
Review-Url: https://codereview.chromium.org/2871523002
Cr-Commit-Position: refs/heads/master@{#470344}
Committed: https://chromium.googlesource.com/chromium/src/+/edb20606028c861740ec4135481db9e214de5be6

[tzik, 2017-05-08 11:01:04]

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

[commit-bot: I haz the power, 2017-05-08 11:01:24]

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, 2017-05-08 13:10:15]

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

[commit-bot: I haz the power, 2017-05-08 13:10:16]

Dry run: This issue passed the CQ dry run.

[tzik, 2017-05-09 09:17:47]

Description was changed from

==========
Use OnceCallback on Mojo interfaces in //content
==========

to

==========
Use OnceCallback on Mojo interfaces in //content

This CL flips `use_once_calback` flag on the Mojo code generator, and
fixes all compile errors after it. After this CL, Mojo interfaces in
//content starts using base::OnceCallback instead of base::Callback
on its return value handling.

The migration recipe was:
 - Convert pass-by-ref callback objects to pass-by-value.
 - Use std::move() to forward it to other consumer, or to invoke it
   with Callback::Run().
 - Handle wherever copies are required manually.
 - Check if the conversion doesn't change the semantics. As the transfer
   and invocation clobber the callback object, care about use-after-move.
   It's considered safe to consume almost scoped-out callback.

BUG=714018
==========

[tzik, 2017-05-09 09:18:12]

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

[commit-bot: I haz the power, 2017-05-09 09:18:39]

Dry run: CQ is trying da patch.

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

[tzik, 2017-05-09 09:18:41]

Description was changed from

==========
Use OnceCallback on Mojo interfaces in //content

This CL flips `use_once_calback` flag on the Mojo code generator, and
fixes all compile errors after it. After this CL, Mojo interfaces in
//content starts using base::OnceCallback instead of base::Callback
on its return value handling.

The migration recipe was:
 - Convert pass-by-ref callback objects to pass-by-value.
 - Use std::move() to forward it to other consumer, or to invoke it
   with Callback::Run().
 - Handle wherever copies are required manually.
 - Check if the conversion doesn't change the semantics. As the transfer
   and invocation clobber the callback object, care about use-after-move.
   It's considered safe to consume almost scoped-out callback.

BUG=714018
==========

to

==========
Use OnceCallback on Mojo interfaces in //content

This CL flips `use_once_calback` flag on the Mojo code generator, and
fixes all compile errors after it. After this CL, Mojo interfaces in
//content starts using base::OnceCallback instead of base::Callback
on its return value handling.

The migration recipe was:
 - Convert pass-by-ref callback objects to pass-by-value.
 - Use std::move() to forward it to other consumer, or to invoke it
   with Callback::Run().
 - Handle wherever copies are required manually.
 - Check if the conversion doesn't change the semantics. As the transfer
   and invocation clobber the callback object, care about use-after-move.
   It's considered safe to consume almost scoped-out callback.

BUG=714018
==========

[tzik, 2017-05-09 09:18:41]

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

[tzik, 2017-05-09 10:27:16]

PTAL

[kinuko, 2017-05-09 11:06:16]

lgtm

[commit-bot: I haz the power, 2017-05-09 11:46:46]

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

[commit-bot: I haz the power, 2017-05-09 11:46:47]

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

[tzik, 2017-05-09 14:15:21]

The CQ bit was checked by tzik@chromium.org

[commit-bot: I haz the power, 2017-05-09 14:15:48]

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, 2017-05-09 15:39:36]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1494339321586090,
"parent_rev": "efd9aa2c88eb30e960c29915dee4e08ea0e7bd97", "commit_rev":
"edb20606028c861740ec4135481db9e214de5be6"}

[commit-bot: I haz the power, 2017-05-09 15:42:14]

Description was changed from

==========
Use OnceCallback on Mojo interfaces in //content

This CL flips `use_once_calback` flag on the Mojo code generator, and
fixes all compile errors after it. After this CL, Mojo interfaces in
//content starts using base::OnceCallback instead of base::Callback
on its return value handling.

The migration recipe was:
 - Convert pass-by-ref callback objects to pass-by-value.
 - Use std::move() to forward it to other consumer, or to invoke it
   with Callback::Run().
 - Handle wherever copies are required manually.
 - Check if the conversion doesn't change the semantics. As the transfer
   and invocation clobber the callback object, care about use-after-move.
   It's considered safe to consume almost scoped-out callback.

BUG=714018
==========

to

==========
Use OnceCallback on Mojo interfaces in //content

This CL flips `use_once_calback` flag on the Mojo code generator, and
fixes all compile errors after it. After this CL, Mojo interfaces in
//content starts using base::OnceCallback instead of base::Callback
on its return value handling.

The migration recipe was:
 - Convert pass-by-ref callback objects to pass-by-value.
 - Use std::move() to forward it to other consumer, or to invoke it
   with Callback::Run().
 - Handle wherever copies are required manually.
 - Check if the conversion doesn't change the semantics. As the transfer
   and invocation clobber the callback object, care about use-after-move.
   It's considered safe to consume almost scoped-out callback.

BUG=714018

Review-Url: https://codereview.chromium.org/2871523002
Cr-Commit-Position: refs/heads/master@{#470344}
Committed:
https://chromium.googlesource.com/chromium/src/+/edb20606028c861740ec4135481d...
==========

[commit-bot: I haz the power, 2017-05-09 15:42:15]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/chromium/src/+/edb20606028c861740ec4135481d...