Get WebRTC resources on Android Testers.

Get WebRTC resources on Android Testers.

I know it is a bit ugly to invoke a script in the WebRTC
checkout like this to download the resources that are needed
for the WebRTC tests, but it's the only way to do this until we've
found a better solution that works both when WebRTC is built
standalone and as a part of Chrome.
I'm working on a better way of downloading the resources
in http://review.webrtc.org/2095004/

There's no easy way to include these files into the archive 
built by zip_build.py since script is made to only include files that
are located in the build_dir (e.g. out/Release).

BUG=webrtc:1882
TEST=ran a local build.
NOTRY=True

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=219774

[kjellander_chromium, 2013-08-27 06:03:14]

This is also needed for https://codereview.chromium.org/17390019/

[Isaac (away), 2013-08-27 06:16:46]

This is fine.  LGTM.

[Isaac (away), 2013-08-27 06:19:01]

I started an android tryjob; feel free to dcommit or CQ w/ NOTRY=True when after
the triggered tests goes green.

[commit-bot: I haz the power, 2013-08-27 12:08:41]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/kjellander@chromium.org/23075028/11001

[commit-bot: I haz the power, 2013-08-27 12:21:46]

Change committed as 219774