test_runner: Migrate MockWebRTCDataChannelHandler to Chromium C++ style.

test_runner: Migrate MockWebRTCDataChannelHandler to Chromium C++ style.

Changes:
1) Run clang-format through source and header files.
2) Fix member variables names.
3) Rename file name to mock_webrtc_data_channel_handler.

BUG=360000
TEST=None. No functional changes.

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=274014

[Nikhil, 2014-05-29 13:55:11]

PTAL. Thanks!

If you have any review comments, then please let me know. I'll rework to
incorporate them.

[Nikhil, 2014-05-30 07:36:24]

Adding Dirk and Abarth for review. PTAL. Thanks!

If you've review comments then please let me know. I'll incorporate them.

[Dirk Pranke, 2014-05-30 18:25:13]

it doesn't look like you actually changed any of the naming styles in the file;
were you planning to do that in a follow up patch?

[Dirk Pranke, 2014-05-30 20:32:45]

On 2014/05/30 18:25:13, Dirk Pranke wrote:
> it doesn't look like you actually changed any of the naming styles in the
file;
> were you planning to do that in a follow up patch?

Sorry, I was referring specifically to the function names. 

Nikhil pointed out that those were inherited from the base class, which is still
in Blink and hence needs to follow the Blink coding style (which I missed).

lgtm.

[Nikhil, 2014-05-30 21:45:00]

The CQ bit was checked by n.bansal@samsung.com

[commit-bot: I haz the power, 2014-05-30 21:49:53]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/n.bansal@samsung.com/305923002/1

[commit-bot: I haz the power, 2014-05-31 04:27:15]

Change committed as 274014