praekelt/vumi-go — pull request #726 by jerith (2013-10-03 19:09:05+00:00)
Title: Jsbox is not happy when there's no Javascript to run.

```
2013-10-03 12:47:02+0000 [HTTP11ClientProtocol,client] Unhandled error in Deferred:
2013-10-03 12:47:02+0000 [HTTP11ClientProtocol,client] Unhandled Error
Traceback (most recent call last):
File "/var/praekelt/vumi-go/ve/local/lib/python2.7/site-packages/twisted/internet/defer.py", line 1070, in _inlineCallbacks
result = g.send(result)
File "/var/praekelt/vumi-go/ve/src/vumi/vumi/application/sandbox.py", line 854, in process_message_in_sandbox
status = yield self._process_in_sandbox(sandbox_protocol, sandbox_init)
File "/var/praekelt/vumi-go/ve/src/vumi/vumi/application/sandbox.py", line 843, in _process_in_sandbox
d.addCallbacks(on_start, log.error)
File "/var/praekelt/vumi-go/ve/local/lib/python2.7/site-packages/twisted/internet/defer.py", line 293, in addCallbacks
self._runCallbacks()
--- ---
File "/var/praekelt/vumi-go/ve/local/lib/python2.7/site-packages/twisted/internet/defer.py", line 575, in _runCallbacks
current.result = callback(current.result, *args, **kw)
File "/var/praekelt/vumi-go/ve/src/vumi/vumi/application/sandbox.py", line 836, in on_start
sandbox_protocol.api.sandbox_init()
File "/var/praekelt/vumi-go/ve/src/vumi/vumi/application/sandbox.py", line 624, in sandbox_init
resource.sandbox_init(self)
File "/var/praekelt/vumi-go/ve/src/vumi/vumi/application/sandbox.py", line 412, in sandbox_init
javascript = self.app_worker.javascript_for_api(api)
File "/var/praekelt/vumi-go/ve/src/vumi/vumi/application/sandbox.py", line 966, in javascript_for_api
return api.config.javascript
File "/var/praekelt/vumi-go/go/apps/jsbox/vumi_app.py", line 37, in javascript
return self.jsbox['javascript']
exceptions.TypeError: 'NoneType' object has no attribute '__getitem__'

```