title: Does destroying GtkBuilder destroy all created widgets?
body: <p>Question regarding GtkBuilder.
  When we unref builder pointer does it destroys all the screens/widgets the builder had created? </p>
  
  <pre><code>if( builder_ptr )
      g_object_unref(G_OBJECT(builder_ptr));
  </code></pre>
  
  <p>Suppose we have created one screen using Glade/XML with some 2-3 top_level windows in it  </p>
  
  <pre><code>gtk_builder_add_from_file(builder_ptr, "Test.glade", &amp;error )
  </code></pre>
  
  <p>and generated GtkBuilder pointer (as above) so after deleting this pointer does it deletes created Windows or do we need to manually delete these windows?</p>
  
  <p>Thanks,<br>
  PP.</p>