title: Failed to set the ‘_$visited’ property on ‘DOMStringMap’: ‘data-_$visited’ is not a valid attribute name
body: <p>We are using breeze.js with entity framework to initiate client side entity management. </p>
  
  <p>We randomly get "Failed to set the ‘<em>$visited’ property on ‘DOMStringMap’: ‘data-</em>$visited’ is not a valid attribute name" error the the breeze.js from __toJSONSafe method of it.</p>
  
  <p>does anybody have any idea what could make "obj._$visited" property undefined? It is coming up as undefined and that is causing the issue during call to the saveChanges()</p>