Remove unused User/Users strings from the profiles UI

Remove unused User/Users strings from the profiles UI

The strings stopped being used in https://codereview.chromium.org/611033002/

XIB changes: use a different string ID for the profiles menu in the menu bar.

BUG=405988
Committed: https://crrev.com/78972ce288b09e91e0e56e1a13a848c53ea3621a
Cr-Commit-Position: refs/heads/master@{#297422}

[noms (inactive), 2014-09-29 15:25:12]

noms@chromium.org changed reviewers:
+ asvitkine@chromium.org, dbeam@chromium.org

[noms (inactive), 2014-09-29 15:25:12]

Hiya,

This is the cleanup strings CL referenced in
https://codereview.chromium.org/611033002/. Please take a look. Thanks!

[Dan Beam, 2014-09-29 18:53:27]

lgtm

[Alexei Svitkine (slow), 2014-09-29 18:55:57]

lgtm

[noms (inactive), 2014-09-29 21:33:45]

The CQ bit was checked by noms@chromium.org

[commit-bot: I haz the power, 2014-09-29 21:34:50]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/603023004/1

[noms (inactive), 2014-09-29 21:35:14]

The CQ bit was unchecked by noms@chromium.org

[noms (inactive), 2014-09-30 14:10:07]

The CQ bit was checked by noms@chromium.org

[commit-bot: I haz the power, 2014-09-30 14:10:39]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/603023004/20001

[commit-bot: I haz the power, 2014-09-30 14:54:02]

Committed patchset #2 (id:20001) as 9aaaf35d9f5d126a5faa9b47e8337c24146550ae

[commit-bot: I haz the power, 2014-09-30 14:54:55]

Patchset 2 (id:??) landed as
https://crrev.com/78972ce288b09e91e0e56e1a13a848c53ea3621a
Cr-Commit-Position: refs/heads/master@{#297422}