use namespace base for base::make_optional in docs

use namespace base for base::make_optional in docs

BUG=none
TBR=mlamouri@chromium.org

Review-Url: https://codereview.chromium.org/2749983002
Cr-Commit-Position: refs/heads/master@{#456964}
Committed: https://chromium.googlesource.com/chromium/src/+/4a9c82efe768ec239706ef632b95c1c6b22ab72d

[michaelpg, 2017-03-15 02:30:19]

Description was changed from

==========
add base:: to helper function name in docs

BUG=none
TBR=mlamouri@chromium.org
==========

to

==========
use namespace base for base::make_optional in docs

BUG=none
TBR=mlamouri@chromium.org
==========

[michaelpg, 2017-03-15 02:30:38]

The CQ bit was checked by michaelpg@chromium.org

[commit-bot: I haz the power, 2017-03-15 02:31:18]

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, 2017-03-15 02:44:30]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1489545038461760, "parent_rev":
"5f6ee0e6d3847f0434495e7a40a618fb0eecf27b", "commit_rev":
"4a9c82efe768ec239706ef632b95c1c6b22ab72d"}

[commit-bot: I haz the power, 2017-03-15 02:45:21]

Description was changed from

==========
use namespace base for base::make_optional in docs

BUG=none
TBR=mlamouri@chromium.org
==========

to

==========
use namespace base for base::make_optional in docs

BUG=none
TBR=mlamouri@chromium.org

Review-Url: https://codereview.chromium.org/2749983002
Cr-Commit-Position: refs/heads/master@{#456964}
Committed:
https://chromium.googlesource.com/chromium/src/+/4a9c82efe768ec239706ef632b95...
==========

[commit-bot: I haz the power, 2017-03-15 02:45:22]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/4a9c82efe768ec239706ef632b95...

[mlamouri (slow - plz ping), 2017-03-15 09:57:32]

lgtm