Clean up perftesthelper.js style

Clean up perftesthelper.js style

This change makes tools/perf/page_sets/tough_animation_cases/resources/perftesthelper.js
consistent with the Chromium Javascript style guide:
 - Fixed indentation
 - Added missing semicolon
 - Renamed file to be underscore separated

Committed: https://crrev.com/9f85387cb8ce5504e84f99c23b3bfb2cd9a3b33b
Cr-Commit-Position: refs/heads/master@{#318358}

[alancutter (OOO until 2018), 2015-02-26 05:05:09]

alancutter@chromium.org changed reviewers:
+ qyearsley@chromium.org

[alancutter (OOO until 2018), 2015-02-26 05:05:10]

Whoops, forgot to upload this again.

This is a reupload of: https://codereview.chromium.org/927583005/
Missed renames fixed now.

[qyearsley, 2015-02-26 16:32:48]

On 2015/02/26 05:05:10, alancutter wrote:
> Whoops, forgot to upload this again.
> 
> This is a reupload of: https://codereview.chromium.org/927583005/
> Missed renames fixed now.

LGTM :-)

[alancutter (OOO until 2018), 2015-02-26 22:13:39]

The CQ bit was checked by alancutter@chromium.org

[commit-bot: I haz the power, 2015-02-26 22:14:32]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/956193002/1

[commit-bot: I haz the power, 2015-02-27 00:41:13]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-27 00:41:54]

Patchset 1 (id:??) landed as
https://crrev.com/9f85387cb8ce5504e84f99c23b3bfb2cd9a3b33b
Cr-Commit-Position: refs/heads/master@{#318358}