I want to get the access token from Google. The Google API says that to get the access token, send the code and other parameters to token generating page, and the response
Rich Sutton's answer finally worked for me, after I realized that adding access_type=offline
is done on the front end client's request for an authorization code, not the back end request that exchanges that code for an access_token. I've added a comment to his answer and this link at Google for more info about refreshing tokens.
P.S. If you are using Satellizer, here is how to add that option to the $authProvider.google in AngularJS.