Mechanical rename of tracing includes for /content [1/3]

Mechanical rename of tracing includes for /content [1/3]

This is just a mechanical rename of tracing includes.
See crrev.com/837303004 and the related bug for motivations.

BUG=451032
TBR=avi@chromium.org

Committed: https://crrev.com/3e765617642274ddf12ddce597e9872dca5a9e5f
Cr-Commit-Position: refs/heads/master@{#313421}

[ssid, 2015-01-27 13:28:23]

ssid@chromium.org changed reviewers:
+ picksi@chromium.org, primiano@chromium.org

[Primiano Tucci (use gerrit), 2015-01-27 16:46:28]

Since you are splitting this in more than one CL, please add [1/3] to the title
of the CL.

LGTM.

Considered the mechanical nature of the change, I think it's safe to TBR this.

[Primiano Tucci (use gerrit), 2015-01-28 00:11:21]

The CQ bit was checked by primiano@chromium.org

[commit-bot: I haz the power, 2015-01-28 00:11:30]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/866803003/1

[commit-bot: I haz the power, 2015-01-28 04:04:15]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-01-28 04:06:31]

Patchset 1 (id:??) landed as
https://crrev.com/3e765617642274ddf12ddce597e9872dca5a9e5f
Cr-Commit-Position: refs/heads/master@{#313421}