Log trace event for webfont decode

Log trace event for webfont decode

This will make it easy to tell when the main thread is busy decoding
webfonts.

BUG=none

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=200627

[Kunihiko Sakamoto, 2015-05-28 08:18:25]

ksakamoto@chromium.org changed reviewers:
+ bashi@chromium.org, eae@chromium.org

[bashi, 2015-05-29 00:54:12]

lgtm

[Kunihiko Sakamoto, 2015-06-02 01:26:22]

eae@: Could you take a look?

[Kunihiko Sakamoto, 2015-06-09 01:36:31]

On 2015/06/02 01:26:22, Kunihiko Sakamoto wrote:
> eae@: Could you take a look?

ping?

[Kunihiko Sakamoto, 2015-08-14 09:53:33]

ksakamoto@chromium.org changed reviewers:
+ drott@chromium.org

[Kunihiko Sakamoto, 2015-08-14 09:53:34]

Hi Dominik,
Could you do OWNER's review?

[eae, 2015-08-14 17:41:42]

LGTM for owners

[Kunihiko Sakamoto, 2015-08-17 01:51:07]

Thanks!

[Kunihiko Sakamoto, 2015-08-17 01:51:12]

The CQ bit was checked by ksakamoto@chromium.org

[Kunihiko Sakamoto, 2015-08-17 01:51:12]

The patchset sent to the CQ was uploaded after l-g-t-m from eae@chromium.org,
bashi@chromium.org
Link to the patchset: https://codereview.chromium.org/1161923003/#ps20001
(title: "rebase")

[commit-bot: I haz the power, 2015-08-17 01:51:20]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1161923003/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1161923003/20001

[commit-bot: I haz the power, 2015-08-17 04:14:48]

Committed patchset #2 (id:20001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=200627