Add trace event for phantom handle processing callback.

Add trace event for phantom handle processing callback.

BUG=chromium:608312
LOG=NO

Committed: https://crrev.com/bc5794e0ee27a25ae73b8edd3d2ce6523c226fb9
Cr-Commit-Position: refs/heads/master@{#35933}

[ulan, 2016-05-02 12:26:45]

ulan@chromium.org changed reviewers:
+ jochen@chromium.org

[ulan, 2016-05-02 12:26:45]

ptal

[jochen (gone - plz use gerrit), 2016-05-02 12:29:17]

lgtm

[ulan, 2016-05-02 12:38:46]

The CQ bit was checked by ulan@chromium.org

[commit-bot: I haz the power, 2016-05-02 12:38:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1934993002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1934993002/1

[commit-bot: I haz the power, 2016-05-02 13:04:34]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-05-02 13:05:00]

Description was changed from

==========
Add trace event for phantom handle processing callback.

BUG=chromium:608312
LOG=NO
==========

to

==========
Add trace event for phantom handle processing callback.

BUG=chromium:608312
LOG=NO

Committed: https://crrev.com/bc5794e0ee27a25ae73b8edd3d2ce6523c226fb9
Cr-Commit-Position: refs/heads/master@{#35933}
==========

[commit-bot: I haz the power, 2016-05-02 13:05:01]

Patchset 1 (id:??) landed as
https://crrev.com/bc5794e0ee27a25ae73b8edd3d2ce6523c226fb9
Cr-Commit-Position: refs/heads/master@{#35933}