title: Knockout - custom binding inside `with` tag - how to pass "$root " to custom binding?
body: <p>I have a custom binding inside <code>with</code> tag </p>
  
  <pre><code>&lt;div id="mapContainer" data-bind="with: contentTabs"&gt;
    ............
              &lt;div id="map" data-bind="createMap: { }"&gt;&lt;/div&gt;
    ............
  &lt;/div&gt;
  </code></pre>
  
  <p>The custom binding is defined as follows</p>
  
  <pre><code>ko.bindingHandlers.createMap = {
      init: function(element, valueAccessor, allBindingsAccessor, viewModel) {
         //Some code which accesses the viewModel
         ....
      }
  }
  </code></pre>
  
  <p>"viewModel" parameter of the custom binding refers to "contentTabs" variable (defined in "with" binding above).</p>
  
  <p>I want to access the view model (root) from the  custom binding in a clean way.</p>
  
  <p>Is it possible?</p>
  
  <p>The code worked well before I wrapped the custom binding by "with" binding.
  - how to pass "$root " to custom binding?</p>