Move content_settings_custom_extension_provider.* to c/b/extensions/api/content_settings/

Move content_settings_custom_extension_provider.* to c/b/extensions/api/content_settings/

This CL moves content_settings_custom_extension_provider.* to
chrome/browser/extensions/api/content_settings/. The detailed discussion
can be seen here: https://code.google.com/p/chromium/issues/detail?id=393202

BUG=384868
Committed: https://crrev.com/21b896c69fa515ec727ce45e6e4b538d12c4559d
Cr-Commit-Position: refs/heads/master@{#305408}

[Sunil Ratnu, 2014-11-21 04:28:02]

sunil.ratnu@samsung.com changed reviewers:
+ kalman@chromium.org, vabr@chromium.org

[Sunil Ratnu, 2014-11-21 04:29:16]

sunil.ratnu@samsung.com changed reviewers:
+ markusheintz@chromium.org

[Sunil Ratnu, 2014-11-21 04:29:30]

Please review this.

Thanks!
Sunil

[vabr (Chromium), 2014-11-21 09:36:14]

Thanks, Sunil Ratnu.
This LGTM.
Vaclav

[not at google - send to devlin, 2014-11-21 21:08:05]

Thanks for doing this! lgtm.

[Sunil Ratnu, 2014-11-24 09:16:07]

On 2014/11/21 21:08:05, kalman wrote:
> Thanks for doing this! lgtm.

Hi Marcus, Could you also please review this?

Thanks!
Sunil

[markusheintz_, 2014-11-24 09:25:26]

On 2014/11/24 09:16:07, Sunil Ratnu wrote:
> On 2014/11/21 21:08:05, kalman wrote:
> > Thanks for doing this! lgtm.
> 
> Hi Marcus, Could you also please review this?
> 
> Thanks!
> Sunil

LGTM

[Sunil Ratnu, 2014-11-24 09:25:50]

The CQ bit was checked by sunil.ratnu@samsung.com

[commit-bot: I haz the power, 2014-11-24 09:26:41]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/748723002/1

[commit-bot: I haz the power, 2014-11-24 10:09:34]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-11-24 10:10:23]

Patchset 1 (id:??) landed as
https://crrev.com/21b896c69fa515ec727ce45e6e4b538d12c4559d
Cr-Commit-Position: refs/heads/master@{#305408}