Use emplace_back in RTree::Build

Use emplace_back in RTree::Build

By using emplace_back istead os push_back we don't have to copy the elements
into the vector.

| Test                     | Before (runs/s)      | After (runs/s)       |
| rtree_construct: 100=    | 40609.00390625       | 45958.69140625       |
| rtree_construct: 1000=   |  4720.29833984375    |  5390.62841796875    |
| rtree_construct: 10000=  |   456.375244140625   |   516.6461791992188  |
| rtree_construct: 100000= |    45.47178268432617 |    51.81435012817383 |

CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel

Review-Url: https://codereview.chromium.org/2871183002
Cr-Commit-Position: refs/heads/master@{#470909}
Committed: https://chromium.googlesource.com/chromium/src/+/3dc8481c601fd89ae33a6defededf5875f5ba65e

[dbatyai, 2017-05-10 12:14:00]

Description was changed from

==========
Use emplace_back in RTree::Build

By using emplace_back istead os push_back we don't have to copy the elements
into the vector.

| Test                     | Before (runs/s)      | After (runs/s)       |
| rtree_construct: 100=    | 40609.00390625       | 45958.69140625       |
| rtree_construct: 1000=   |  4720.29833984375    |  5390.62841796875    |
| rtree_construct: 10000=  |   456.375244140625   |   516.6461791992188  |
| rtree_construct: 100000= |    45.47178268432617 |    51.81435012817383 |
==========

to

==========
Use emplace_back in RTree::Build

By using emplace_back istead os push_back we don't have to copy the elements
into the vector.

| Test                     | Before (runs/s)      | After (runs/s)       |
| rtree_construct: 100=    | 40609.00390625       | 45958.69140625       |
| rtree_construct: 1000=   |  4720.29833984375    |  5390.62841796875    |
| rtree_construct: 10000=  |   456.375244140625   |   516.6461791992188  |
| rtree_construct: 100000= |    45.47178268432617 |    51.81435012817383 |
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
==========

[dbatyai, 2017-05-10 13:59:27]

Description was changed from

==========
Use emplace_back in RTree::Build

By using emplace_back istead os push_back we don't have to copy the elements
into the vector.

| Test                     | Before (runs/s)      | After (runs/s)       |
| rtree_construct: 100=    | 40609.00390625       | 45958.69140625       |
| rtree_construct: 1000=   |  4720.29833984375    |  5390.62841796875    |
| rtree_construct: 10000=  |   456.375244140625   |   516.6461791992188  |
| rtree_construct: 100000= |    45.47178268432617 |    51.81435012817383 |
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
==========

to

==========
Use emplace_back in RTree::Build

By using emplace_back istead os push_back we don't have to copy the elements
into the vector.

| Test                     | Before (runs/s)      | After (runs/s)       |
| rtree_construct: 100=    | 40609.00390625       | 45958.69140625       |
| rtree_construct: 1000=   |  4720.29833984375    |  5390.62841796875    |
| rtree_construct: 10000=  |   456.375244140625   |   516.6461791992188  |
| rtree_construct: 100000= |    45.47178268432617 |    51.81435012817383 |

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

[dbatyai, 2017-05-10 13:59:28]

dbatyai@inf.u-szeged.hu changed reviewers:
+ vmpstr@chromium.org

[vmpstr, 2017-05-10 18:03:15]

lgtm, thanks

[dbatyai, 2017-05-11 09:25:34]

The CQ bit was checked by dbatyai@inf.u-szeged.hu

[commit-bot: I haz the power, 2017-05-11 09:26:30]

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, 2017-05-11 10:47:41]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1494494734476050, "parent_rev":
"defdfbc63904f49b29947f3a51babfe1f00f23b8", "commit_rev":
"3dc8481c601fd89ae33a6defededf5875f5ba65e"}

[commit-bot: I haz the power, 2017-05-11 10:47:53]

Description was changed from

==========
Use emplace_back in RTree::Build

By using emplace_back istead os push_back we don't have to copy the elements
into the vector.

| Test                     | Before (runs/s)      | After (runs/s)       |
| rtree_construct: 100=    | 40609.00390625       | 45958.69140625       |
| rtree_construct: 1000=   |  4720.29833984375    |  5390.62841796875    |
| rtree_construct: 10000=  |   456.375244140625   |   516.6461791992188  |
| rtree_construct: 100000= |    45.47178268432617 |    51.81435012817383 |

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

to

==========
Use emplace_back in RTree::Build

By using emplace_back istead os push_back we don't have to copy the elements
into the vector.

| Test                     | Before (runs/s)      | After (runs/s)       |
| rtree_construct: 100=    | 40609.00390625       | 45958.69140625       |
| rtree_construct: 1000=   |  4720.29833984375    |  5390.62841796875    |
| rtree_construct: 10000=  |   456.375244140625   |   516.6461791992188  |
| rtree_construct: 100000= |    45.47178268432617 |    51.81435012817383 |

CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel

Review-Url: https://codereview.chromium.org/2871183002
Cr-Commit-Position: refs/heads/master@{#470909}
Committed:
https://chromium.googlesource.com/chromium/src/+/3dc8481c601fd89ae33a6defeded...
==========

[commit-bot: I haz the power, 2017-05-11 10:47:54]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/3dc8481c601fd89ae33a6defeded...