run the webtry build script instead of using go build

run the webtry build script instead of using go build

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/9f58dd047c4acd49baa54f9357b7519d5e69e6dc

[humper, 2014-09-25 13:11:29]

humper@google.com changed reviewers:
+ jcgregorio@google.com

[humper, 2014-09-25 13:11:37]

ptal

[humper, 2014-09-25 13:11:45]

The CQ bit was checked by humper@google.com

[humper, 2014-09-25 13:11:48]

The CQ bit was unchecked by humper@google.com

[humper, 2014-09-25 13:11:50]

The CQ bit was checked by humper@google.com

[commit-bot: I haz the power, 2014-09-25 13:12:09]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/601203002/1

[commit-bot: I haz the power, 2014-09-25 13:12:10]

Note for Reviewers:
The CQ is waiting for an approval.
If you believe that the CL is not ready yet, or if you would like to L-G-T-M
with comments then please uncheck the CQ checkbox.

Waiting for LGTM from a valid reviewer till 2014-09-25 19:12 UTC

[commit-bot: I haz the power, 2014-09-25 13:15:28]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-09-25 13:15:29]

Try jobs failed on following builders:
  Build-Win-VS2013-x86-Debug-Trybot on tryserver.skia
(http://108.170.220.76:10117/builders/Build-Win-VS2013-x86-Debug-Trybot/builds...)

[jcgregorio, 2014-09-29 14:32:41]

On 2014/09/25 13:15:29, I haz the power (commit-bot) wrote:
> Try jobs failed on following builders:
>   Build-Win-VS2013-x86-Debug-Trybot on tryserver.skia
>
(http://108.170.220.76:10117/builders/Build-Win-VS2013-x86-Debug-Trybot/builds...)

LGTM

[jcgregorio, 2014-09-29 14:32:44]

The CQ bit was checked by jcgregorio@google.com

[commit-bot: I haz the power, 2014-09-29 14:33:19]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/601203002/20001

[commit-bot: I haz the power, 2014-09-29 14:40:44]

Committed patchset #2 (id:20001) as 9f58dd047c4acd49baa54f9357b7519d5e69e6dc