Google Accounts Session Missing From Prediction API's API Explorer

[GoogleCodeExporter]

What steps will reproduce the problem?

1. Login to Google
2. Go to API Explorer for the Prediction API @ 
p/prediction/v1.6/prediction.trainedmodels.list
(or 
https://developers.google.com/apis-explorer/#p/prediction/v1.6/prediction.traine
dmodels.list)
3. Notice it no longer recognises you as logged in
4. Authorize via OAuth2 -- have it work once
5. Reload the API Explorer page after going back to review some Documentation
6. See that you are no longer recognised (again)
7. Try to make sense out of this? lol

What is the expected output? What do you see instead?

This is what I see, despite creating OAuth2 authorisations (twice):
{
 "error": {
  "errors": [
   {
    "domain": "global",
    "reason": "required",
    "message": "Login Required",
    "locationType": "header",
    "location": "Authorization"
   }
  ],
  "code": 401,
  "message": "Login Required"
 }
}

What version of the product are you using? On what operating system?

From my Google Apps account, info@audiopoison.com, I am using OSX Mountain Lion 
12F45, Safari Version 6.1.6 (8537.78.1)

Please provide any additional information below.

n/a

Original issue reported on code.google.com by i...@audiopoison.com on 6 Sep 2014 at 2:15