title: How to detect if Google account hasn't Gmail
body: <p>How can I recognize Google accounts without Gmail?</p>
  
  <p>I use OAuth2 for authorization and then download user messages.
  But if Google account hasn't Gmail, then I receive the error while getting data from api:
      {
          "errors": [
          {
              "domain": "global",
              "reason": "failedPrecondition",
              "message": "Bad Request"
          }
          ],
          "code": 400,
          "message": "Bad Request"
      }</p>
  
  <p>What is the best way to detect accounts without Gmail?
  Now I just send test GET request to gmail-api and check that it returns OK.
  But I'm looking for best solution.</p>