I'm currently experimenting with a Google App Engine/Go + Polymer.dart website at http://xclamm.appspot.com/.
The problem is that I get the following error when I access http://xclamm.appspot.com/ with Dartium (31.0.1612.0 Developer Build 219647).
XMLHttpRequest cannot load https://talkgadget.google.com/talkgadget/channel.js. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://xclamm.appspot.com' is therefore not allowed access.
I did some research and found that the problem is related with how I refer to
/_ah/channel/jsapi, but I can't find how to fix it. I tried the following ways to refer to channel.js, but I still get the same error.
If I run the website on dev_appserver.py, it seems to be working OK. Am I missing something?
The source code is available at https://github.com/rillomas/xclamm-gae, and I'm using Google App Engine SDK 1.8.4 for Go (x64 Windows).