Change flat_tree::unsafe_emplace to actually emplace

Change flat_tree::unsafe_emplace to actually emplace

This change modifies base::flat_tree::unsafe_emplace to do an emplace instead of an insert under the hood.

BUG=671759
Review-Url: https://codereview.chromium.org/2792343002
Cr-Commit-Position: refs/heads/master@{#461863}
Committed: https://chromium.googlesource.com/chromium/src/+/f7d92cff18cba731d3a33d19d3f9595bbacd6fb6

[jdoerrie, 2017-04-04 12:24:35]

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

[commit-bot: I haz the power, 2017-04-04 12:24:46]

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, 2017-04-04 13:52:01]

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

[commit-bot: I haz the power, 2017-04-04 13:52:02]

Dry run: This issue passed the CQ dry run.

[jdoerrie, 2017-04-04 14:13:40]

Description was changed from

==========
Change flat_tree::unsafe_emplace to actually emplace

BUG=671759
==========

to

==========
Change flat_tree::unsafe_emplace to actually emplace

This change modifies base::flat_tree::unsafe_emplace to do an emplace instead of
an insert under the hood.

BUG=671759
==========

[jdoerrie, 2017-04-04 14:13:40]

jdoerrie@chromium.org changed reviewers:
+ brettw@chromium.org, dyaroshev@yandex-team.ru

[jdoerrie, 2017-04-04 14:14:13]

Dear both, please review.

https://codereview.chromium.org/2792343002/diff/1/base/containers/flat_tree.h
File base/containers/flat_tree.h (right):

https://codereview.chromium.org/2792343002/diff/1/base/containers/flat_tree.h...
base/containers/flat_tree.h:687: std::forward<Args>(args)...);
There was some discussion in the emplace thread claiming that sometimes
explicitly constructing the type is clearer and worth more than the small
performance cost of doing an extra move
(https://groups.google.com/a/chromium.org/forum/#!topic/cxx/m3cblzEta7A).

However, I think given that this is library code and this particular method is
not supposed to be called directly by customers we should try to be efficient as
possible.

[dyaroshev, 2017-04-04 15:48:21]

LGTM

https://codereview.chromium.org/2792343002/diff/1/base/containers/flat_tree.h
File base/containers/flat_tree.h (right):

https://codereview.chromium.org/2792343002/diff/1/base/containers/flat_tree.h...
base/containers/flat_tree.h:687: std::forward<Args>(args)...);
On 2017/04/04 14:14:13, jdoerrie wrote:
> There was some discussion in the emplace thread claiming that sometimes
> explicitly constructing the type is clearer and worth more than the small
> performance cost of doing an extra move
> (https://groups.google.com/a/chromium.org/forum/#!topic/cxx/m3cblzEta7A).
> 
> However, I think given that this is library code and this particular method is
> not supposed to be called directly by customers we should try to be efficient
as
> possible.

This wasn't the intention (at least from my point of view).

[brettw, 2017-04-04 18:19:06]

lgtm

[jdoerrie, 2017-04-04 21:48:33]

The CQ bit was checked by jdoerrie@chromium.org

[commit-bot: I haz the power, 2017-04-04 21:49:31]

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, 2017-04-04 22:12:07]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1491342513835210, "parent_rev":
"c1c5dd7976c915d9fbd6e6c9526f5b3b45895e72", "commit_rev":
"f7d92cff18cba731d3a33d19d3f9595bbacd6fb6"}

[commit-bot: I haz the power, 2017-04-04 22:12:55]

Description was changed from

==========
Change flat_tree::unsafe_emplace to actually emplace

This change modifies base::flat_tree::unsafe_emplace to do an emplace instead of
an insert under the hood.

BUG=671759
==========

to

==========
Change flat_tree::unsafe_emplace to actually emplace

This change modifies base::flat_tree::unsafe_emplace to do an emplace instead of
an insert under the hood.

BUG=671759

Review-Url: https://codereview.chromium.org/2792343002
Cr-Commit-Position: refs/heads/master@{#461863}
Committed:
https://chromium.googlesource.com/chromium/src/+/f7d92cff18cba731d3a33d19d3f9...
==========

[commit-bot: I haz the power, 2017-04-04 22:12:55]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/f7d92cff18cba731d3a33d19d3f9...