code: public static boolean isEmailableFrom(String email, String syncAccountName) {
          return Utils.isValidEmail(email) && !email.equals(syncAccountName);
      }
docs: Returns true if:
  (1) the email is not a resource like a conference room or another calendar.
  Catch most of these by filtering out suffix calendar.google.com.
  (2) the email is not equal to the sync account to prevent mailing himself.