title: Why is Object.keys not Object.prototype.keys?
body: <p>I'm wondering why the spec has defined <code>Object.keys</code> instead of <code>Object.prototype.keys</code>? it would surely be much better if the API was consistent, and I would like to understand why that is not the case.</p>
  
  <p>Other methods are on <code>Object.prototype</code>, so why is this not the case?</p>