title: Extending DataGridColumn and specifying paddingLeft
body: <p>I'm tring to Extend DataGridColumn, and in the extending class, trying<br>
  to specify a value for paddingLeft, but I am unable to compile it.</p>
  
  <p>Using Flex Builder 3 :   </p>
  
  <p>mainApp.mxml : </p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" xmlns:local="*"&gt;
      &lt;mx:DataGrid x="191" y="171"&gt;
          &lt;mx:columns&gt;
              &lt;local:DataGridColumnExt headerText="Column 1" dataField="col1"/&gt;
          &lt;/mx:columns&gt;
      &lt;/mx:DataGrid&gt;
  &lt;/mx:Application&gt;
  </code></pre>
  
  <p>DataGridColumnExt.mxml :  </p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;mx:DataGridColumn xmlns="*" xmlns:mx="http://www.adobe.com/2006/mxml" paddingLeft="10"&gt;
  &lt;/mx:DataGridColumn&gt;
  </code></pre>
  
  <p>Error I get :<br>
  Access of possibly undefined property styleDeclaration through a reference with static type DataGridColumnExt. [Generated code (use -keep to save): Path: DataGridColumnExt-generated.as, Line: 68, Column: 13]     DataGridColumnWithLeftPadding   Unknown 1290353024334   24677</p>