Fix SDK forward declarations after CL 530193004

Fix SDK forward declarations after CL 530193004

The APIs that need forward declarations were actually introduced in
OS X 10.7 SDK instead of 10.9 SDK, forward declare them in the wrong
place will cause build issue when using older SDKs like 10.7 or 10.8.

BUG=390212
Committed: https://crrev.com/59c4ad104b6f03af9c9acffc0fd9a42707083390
Cr-Commit-Position: refs/heads/master@{#294013}

[Jiang Jiang, 2014-09-09 15:47:44]

jiangj@opera.com changed reviewers:
+ rsesek@chromium.org

[Robert Sesek, 2014-09-09 15:57:10]

LGTM

[Jiang Jiang, 2014-09-09 18:34:28]

The CQ bit was checked by jiangj@opera.com

[commit-bot: I haz the power, 2014-09-09 18:39:34]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jiangj@opera.com/555163002/1

[Jiang Jiang, 2014-09-09 18:59:02]

The CQ bit was unchecked by jiangj@opera.com

[Jiang Jiang, 2014-09-09 19:04:45]

The CQ bit was checked by jiangj@opera.com

[commit-bot: I haz the power, 2014-09-09 19:09:15]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jiangj@opera.com/555163002/40001

[commit-bot: I haz the power, 2014-09-09 21:30:14]

Committed patchset #3 (id:40001) as 90624c55ad6422ca6853e3bb7932b7a4f5982995

[Jiang Jiang, 2014-09-09 21:55:53]

On 2014/09/09 21:30:14, I haz the power (commit-bot) wrote:
> Committed patchset #3 (id:40001) as 90624c55ad6422ca6853e3bb7932b7a4f5982995

This shows as committed, but I can't find it from
https://chromium.googlesource.com/chromium/src.git, any reason for that?

[Jiang Jiang, 2014-09-09 21:57:46]

On 2014/09/09 21:55:53, Jiang Jiang wrote:
> On 2014/09/09 21:30:14, I haz the power (commit-bot) wrote:
> > Committed patchset #3 (id:40001) as 90624c55ad6422ca6853e3bb7932b7a4f5982995
> 
> This shows as committed, but I can't find it from
> https://chromium.googlesource.com/chromium/src.git, any reason for that?

Now it shows up, there seems to be some delay (~1 hour) between commit-bot and
git master.

[commit-bot: I haz the power, 2014-09-10 03:55:47]

Patchset 3 (id:??) landed as
https://crrev.com/59c4ad104b6f03af9c9acffc0fd9a42707083390
Cr-Commit-Position: refs/heads/master@{#294013}