Bug 120315 If the display property of an item is set to "none", it doesn't take effect in new pdf emitter.
Description: If the display property of an item is set to "null", it doesn't take effect in new pdf emitter. steps to reproduce: 1. Add a label. 2. Open "properties" view. 3. Set section>Display as "none". 4. Preview in PDF. Expected result: the label disappears. Actual result: the label is still visible.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/css/engine/value/birt/VisibleFormatManager.java
{
	/**
	 * The default value.
	 */
	public final static ListValue DEFAULT_VALUE = new ListValue();
	static {
		DEFAULT_VALUE.append(BIRTValueConstants.ALL_VALUE);
	}
	/**