title: Text wrapping expands the column to fit the text
body: <p>I've got a grid defined simply:</p>
  
  <pre><code>&lt;Grid Margin="0,5,0,0"&gt;
    &lt;Grid.ColumnDefinitions&gt;
      &lt;ColumnDefinition Width="50"&gt;&lt;/ColumnDefinition&gt;
      &lt;ColumnDefinition Width="50"&gt;&lt;/ColumnDefinition&gt;
      &lt;ColumnDefinition Width="48"&gt;&lt;/ColumnDefinition&gt;
      &lt;ColumnDefinition Width="Auto"&gt;&lt;/ColumnDefinition&gt;
     &lt;/Grid.ColumnDefinitions&gt;
  </code></pre>
  
  <p>Then I'm trying to bind some content like this:</p>
  
  <pre><code>&lt;TextBlock TextWrapping="Wrap" Grid.Column="3" Text="{Binding Text}"&gt;
  </code></pre>
  
  <p>Set up like this, the text won't wrap. It simply expands the column to fit the text. If I set the Width to a fixed amount on the last column, wrapping works as expected. The problem there is that if the user widens the window, the column stays at a fixed size. How can I get the column to size dynamically with the width of the grid, but still wrap the text within it?</p>