Mojo C++ bindings: change some std::unique_ptr<base::Lock> to base::Optional<base::Lock>.

Mojo C++ bindings: change some std::unique_ptr<base::Lock> to base::Optional<base::Lock>.

This helps to reduce heap allocation.

BUG=651103, 693476
Review-Url: https://codereview.chromium.org/2707483002
Cr-Commit-Position: refs/heads/master@{#451394}
Committed: https://chromium.googlesource.com/chromium/src/+/9ac6e6466cc0df7e1a3ad4488c5c8bdc2db4da36

[yzshen1, 2017-02-17 19:14:10]

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

[yzshen1, 2017-02-17 19:14:57]

yzshen@chromium.org changed reviewers:
+ rockot@chromium.org

[yzshen1, 2017-02-17 19:14:58]

Hi, Ken.

Would you please take a look? Thanks!

[commit-bot: I haz the power, 2017-02-17 19:15:05]

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

[Ken Rockot(use gerrit already), 2017-02-17 19:16:13]

lgtm

[yzshen1, 2017-02-17 19:16:48]

On 2017/02/17 19:16:13, Ken Rockot wrote:
> lgtm

I wonder how fast you can do code reviews!
Thanks!

[yzshen1, 2017-02-17 19:16:55]

The CQ bit was unchecked by yzshen@chromium.org

[yzshen1, 2017-02-17 19:16:55]

The CQ bit was checked by yzshen@chromium.org

[commit-bot: I haz the power, 2017-02-17 19:17:24]

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, 2017-02-17 23:07:55]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1487359015900740, "parent_rev":
"646e9940b5d772c956f344a3c48abf137c0eda45", "commit_rev":
"9ac6e6466cc0df7e1a3ad4488c5c8bdc2db4da36"}

[commit-bot: I haz the power, 2017-02-17 23:08:39]

Description was changed from

==========
Mojo C++ bindings: change some std::unique_ptr<base::Lock> to
base::Optional<base::Lock>.

This helps to reduce heap allocation.

BUG=651103,693476
==========

to

==========
Mojo C++ bindings: change some std::unique_ptr<base::Lock> to
base::Optional<base::Lock>.

This helps to reduce heap allocation.

BUG=651103,693476

Review-Url: https://codereview.chromium.org/2707483002
Cr-Commit-Position: refs/heads/master@{#451394}
Committed:
https://chromium.googlesource.com/chromium/src/+/9ac6e6466cc0df7e1a3ad4488c5c...
==========

[commit-bot: I haz the power, 2017-02-17 23:08:40]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/9ac6e6466cc0df7e1a3ad4488c5c...