Remove unneeded Friend from chrome_metrics_service_accessor

Remove unneeded Friend from chrome_metrics_service_accessor

BUG=

Committed: https://crrev.com/ca032c3aed93e5afd7c32da76147f36a72dc4341
Cr-Commit-Position: refs/heads/master@{#296722}

[csharp, 2014-09-25 15:25:56]

Patchset #1 (id:1) has been deleted

[csharp, 2014-09-25 15:26:26]

csharp@chromium.org changed reviewers:
+ asvitkine@chromium.org

[Alexei Svitkine (slow), 2014-09-25 15:26:57]

lgtm

[csharp, 2014-09-25 15:30:43]

The CQ bit was checked by csharp@chromium.org

[commit-bot: I haz the power, 2014-09-25 15:32:04]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/601243002/20001

[commit-bot: I haz the power, 2014-09-25 16:40:54]

Committed patchset #1 (id:20001) as 3de298049c87606292839628a9b35a0520d74151

[commit-bot: I haz the power, 2014-09-25 16:41:39]

Patchset 1 (id:??) landed as
https://crrev.com/ca032c3aed93e5afd7c32da76147f36a72dc4341
Cr-Commit-Position: refs/heads/master@{#296722}

[MAD, 2014-09-25 19:22:49]

A revert of this CL (patchset #1 id:20001) has been created in
https://codereview.chromium.org/603173003/ by mad@chromium.org.

The reason for reverting is: We need to bring this back since the usage of it is
coming back in an upcoming patch.

Sorry about that...

BYE
MAD
.