Revert of Enable traffic shaping in loading.mobile benchmark

Revert of Enable traffic shaping in loading.mobile benchmark (patchset #1 id:40001 of https://codereview.chromium.org/2493063002/ )

Reason for revert:
loading.mobile started failing after this CL. See http://crbug.com/671640#c10

Original issue's description:
> Enable traffic shaping in loading.mobile benchmark
> 
> After this patch, loading.mobile benchmark will run with two traffic
> configurations:
> 
> - No traffic shaping (as before)
> - "Regular 3G" (Down 750kbps, Up 250kbps, 100ms RTT)
> 
> BUG=664420
> 
> Committed: https://crrev.com/9febcf5133be621b82954c0fea52123fa4f8b7a8
> Cr-Commit-Position: refs/heads/master@{#435230}

TBR=nednguyen@google.com,ksakamoto@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=664420

[dtu, 2016-12-06 20:25:02]

The CQ bit was checked by dtu@chromium.org

[dtu, 2016-12-06 20:25:02]

Created Revert of Enable traffic shaping in loading.mobile benchmark

[commit-bot: I haz the power, 2016-12-06 20:26:00]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[rnephew (Reviews Here), 2016-12-06 20:33:31]

The CQ bit was unchecked by rnephew@chromium.org

[rnephew (Reviews Here), 2016-12-06 20:43:23]

On 2016/12/06 20:26:00, commit-bot: I haz the power wrote:
> CQ is trying da patch. Follow status at
>  
>
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

Unchecked commit, test was timing out due to taking too long with traffic
shaping. Increasing the time to see if that fixes it first.

https://codereview.chromium.org/2556753003/