Hello,
I am new in Tizen.
I am trying to send a XMLHttpRequest to server to create a “whataApp” account by using coseme.js.

I copied the following XMLHttpRequest code from coseme.js for WhatsApp – 
 

var URL = 'https://v.whatsapp.net/v2/' +
                operation + '?' + CoSeMe.utils.urlencode(params);
      logger.log('Request:', URL);

      // Perform the query
     var xhr = new XMLHttpRequest({mozSystem: true});
   xhr.onload = function() {
  logger.log(this.response);
  onready && onready.call(this, this.response);
   };
   xhr.onerror = onerror;
   xhr.open('GET', URL,true);
   xhr.overrideMimeType('json');
   xhr.responseType = 'json';
   xhr.setRequestHeader('User-Agent', CoSeMe.config.tokenData['u']);
   xhr.setRequestHeader('Accept', 'text/json');
   xhr.send();

but it shows the following Error :
  XMLHttpRequest.responseType “json” is not supported.
  
Is responseType json is not supported in Tizen? If supported, then how can I active this for my application?