Bug 128586 Change parameter in drill through link doesn't work in pdf.
Description: Change parameter in drill through link doesn't work in pdf. Steps to reproduce: 1. New a report source and a report target. 2. Insert a report parameter p1 in target.rptdesign, drag it to Layout. 3. Insert a label in source.rptdesign, define a drill through link to target.rptdesign and set p1 to "first". 4. Preview source.rptdesign in pdf and click the link. 5. Revise drill through link to set p1 to "second", then preview in pdf, click the link. Expected result: Target show "second" as value. Actual result: Target still showed "first"
engine/org.eclipse.birt.report.engine.emitter.pdf/src/org/eclipse/birt/report/engine/emitter/pdf/PDFEmitter.java
public void visitText(ITextArea textArea)
	{
		drawText(textArea);
	}
	public void visitImage(IImageArea imageArea)
	{
		drawImage(imageArea);
	}
	/**
	 * If the container is a PageArea, this method news a pdf page.
	 * If the container is the other containerAreas, 
	 * such as TableArea, or just the border of textArea/imageArea
	 * draw the border and background of the container
	 * @param container				the ContainerArea specified from layout
	 */
	public void startContainer(IContainerArea container)
	{
		if (container instanceof PageArea)
		{
			newPage(container);
		}
		else
		{
			drawContainer(container);
		}
	}
	public void endContainer(IContainerArea containerArea)
	{