Bug 151202 [regression]Set default master page to item in cell will cause blank page
Description: Set default master page to item in cell will cause blank page Steps to reproduce: 1. New a report 2. Insert a grid(1*1) 3. Insert a label to grid cell 4. Select the label and set default master page to it 5. Preview in Web Viewer and pdf Expected result: No blank page, just one page for grid display. Actual result: A blank page before grid page
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/layout/pdf/PDFAbstractLM.java
public void cancel( )
	{
		if ( executor != null && status != STATUS_END )
		{
			cancelChildren( );
			executor.close( );
		}
	}
	protected void execute( IReportItemExecutor executor, IContent content )
	{
		if ( executor != null )
		{
			while ( executor.hasNextChild( ) )
			{
				IReportItemExecutor childExecutor = executor.getNextChild( );
				if ( childExecutor != null )
				{
					IContent childContent = childExecutor.execute( );
					content.getChildren( ).add( childContent );
					execute( childExecutor, childContent );
					childExecutor.close( );
				}
			}
		}
	}
	public void setEmitter( IContentEmitter emitter )
	{
		this.emitter = emitter;
	}
	protected class ReportStackingExecutor implements IReportItemExecutor