code: @Deprecated
      public void pushGcmRegistrationId(String gcmId, boolean register) {
          CleverTapAPI cleverTapAPI = weakReference.get();
          if (cleverTapAPI == null) {
              Logger.d("CleverTap Instance is null.");
          } else {
              cleverTapAPI.pushGcmRegistrationId(gcmId, register);
          }
      }
docs: Sends the GCM registration ID to CleverTap.
  
  @param gcmId    The GCM registration ID
  @param register Boolean indicating whether to register
  or not for receiving push messages from CleverTap.
  Set this to true to receive push messages from CleverTap,
  and false to not receive any messages from CleverTap.
  @deprecated use {@link CleverTapAPI#pushGcmRegistrationId(String gcmId, boolean register)}