Include webrtc/base/json.h rather than from jsoncpp directly.

Include webrtc/base/json.h rather than from jsoncpp directly.

This makes us use the clever code that adapts the path depending on where we build, so it works in google3 too.

BUG=None

Committed: https://crrev.com/9d15c66830143e391e605ba9b6350617d047c12b
Cr-Commit-Position: refs/heads/master@{#9752}

[phoglund, 2015-08-18 14:51:12]

phoglund@webrtc.org changed reviewers:
+ tkchin@webrtc.org

[phoglund, 2015-08-18 14:51:13]

AFAIK this should be functionally the same. Tested by building AppRTCDemo and
making sure it can acquire the camera.

[phoglund, 2015-08-19 12:48:21]

phoglund@webrtc.org changed reviewers:
- tkchin@webrtc.org

[phoglund, 2015-08-19 12:49:01]

Hm, I need to do some more thinking about this issue. 

talk/app/webrtc/java/jni/jni_helpers.cc also uses unistr.h.

[phoglund, 2015-08-19 13:55:31]

phoglund@webrtc.org changed reviewers:
+ tkchin@webrtc.org

[phoglund, 2015-08-19 13:55:31]

OK, this could maybe work.

[phoglund, 2015-08-20 16:27:04]

PTAL

[tkchin_webrtc, 2015-08-20 18:57:40]

On 2015/08/20 16:27:04, phoglund wrote:
> PTAL

I know nothing about android device info :) But adding an include seems good to
me.. lgtm
Adding Alex too.

[tkchin_webrtc, 2015-08-20 18:57:53]

tkchin@webrtc.org changed reviewers:
+ glaznev@webrtc.org

[phoglund, 2015-08-21 07:18:00]

All right, I'll just go ahead and commit this then. Alex, let me know if you
have any objections. This is really just a cleanup: our base/json.h is just a
bit more clever about which jsoncpp header it includes, so we include that
rather than including jsoncpp directly.

[phoglund, 2015-08-21 07:18:04]

The CQ bit was checked by phoglund@webrtc.org

[commit-bot: I haz the power, 2015-08-21 07:18:12]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1291283003/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1291283003/40001

[commit-bot: I haz the power, 2015-08-21 08:00:42]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-08-21 08:00:50]

Patchset 3 (id:??) landed as
https://crrev.com/9d15c66830143e391e605ba9b6350617d047c12b
Cr-Commit-Position: refs/heads/master@{#9752}