Google+ share button popup error Claimed origin not in whitelist

Your web origin in the Google API Console should only include http:// or https:// and then the host name. Make sure you don’t have / in the end. The web origin is under the OAuth 2.0 Client ID section in the Console.

Remove the ‘/’ at the end of “Javascript Origins” url and solve

Example:
Original error URL: http://www.example.com/