title: SAPUI5 Custom control does not render updated data at runtime
body: <p>I've created a custom control where I have 5 properties and render a graph based on them like so:</p>
  
  <pre><code>renderer : function(manager, myControl) {
      manager.write("&lt;div&gt;");
      manager.write("Some html stuff");
      manager.write("&lt;/div&gt;");
  }
  </code></pre>
  
  <p>here everything works fine and render the graph with my pre selected model data. The problem comes when I try to change some of the proparties at runtime. In the method <code>rerender</code> the code is triggered when some of the properties are changed but the rendering is not applied. The method itself is identical, just the manager is instanciated.</p>
  
  <pre><code>rerender : function() {
      console.log("trigger");
      var manager = new sap.ui.core.RenderManager();
      manager.write("&lt;div&gt;");
      manager.write("Some html stuff");
      manager.write("&lt;/div&gt;");
  }
  </code></pre>
  
  <p>I also tried to create a global object <code>manager</code> and make both <code>managers</code> in above to be the same thing. The result was the same...</p>