[Extensions Toolbar Mac] Remove ToolbarActionViewDelegateCocoa

[Extensions Toolbar Mac] Remove ToolbarActionViewDelegateCocoa

This class was used for more at one point, but with various refactors to make
more code platform-agnostic, it's been made pretty obsolete. Get rid of it.

BUG=457392
Committed: https://crrev.com/ed1f6906d46de89f87e94c4ab34551a578912bd1
Cr-Commit-Position: refs/heads/master@{#316044}

[Devlin, 2015-02-12 17:26:57]

Patchset #1 (id:1) has been deleted

[Devlin, 2015-02-12 19:11:27]

rdevlin.cronin@chromium.org changed reviewers:
+ avi@chromium.org

[Devlin, 2015-02-12 19:11:28]

Woohoo, less code! :)

[Avi (use Gerrit), 2015-02-12 19:16:51]

lgtm!

[Devlin, 2015-02-12 20:32:22]

The CQ bit was checked by rdevlin.cronin@chromium.org

[commit-bot: I haz the power, 2015-02-12 20:32:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/911203002/20001

[commit-bot: I haz the power, 2015-02-12 20:36:30]

Committed patchset #1 (id:20001)

[commit-bot: I haz the power, 2015-02-12 20:37:41]

Patchset 1 (id:??) landed as
https://crrev.com/ed1f6906d46de89f87e94c4ab34551a578912bd1
Cr-Commit-Position: refs/heads/master@{#316044}