Bug 179931 Provide new interface IStyle to let extension return the style properties values
Provide the IStyle interface to let extension user can return the style property value list for their extension elements.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/elements/strategy/ExtendedItemPropSearchStrategy.java
{
	private final static ExtendedItemPropSearchStrategy instance = new ExtendedItemPropSearchStrategy( );
	/**
	 * Protected constructor.
	 */
	protected ExtendedItemPropSearchStrategy( )
	{
	}
	/**
	 * Returns the instance of <code>ExtendedItemPropSearchStrategy</code>
	 * which provide the specific property searching route for
	 * <code>ExtendedItem</code>.
	 * 
	 * @return the instance of <code>ExtendedItemPropSearchStrategy</code>
	 */
	public static PropertySearchStrategy getInstance( )
	{
		return instance;
	}