Bug 199225 [Automation][Regression] NPE caught when preview attached report in web viewer
steps to reproduce: - use the attached report design - preview in web viewer expected behavior: - report should be rendered properly actual behavior: - NPE caught
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/layout/html/buffer/HTMLPageBuffer.java
break;
			case IContent.CELL_CONTENT:
				BlockStackingNode cellNode = new BlockStackingNode(content, emitter,generator);
				setup(cellNode, isFirst);
				if(currentNode.isStarted( ))
				{
					cellNode.start(  );
				}
				currentNode = cellNode;
				break;
			case IContent.PAGE_CONTENT:
				PageNode pageNode = new PageNode(content, emitter,generator);
				setup(pageNode, isFirst);
				currentNode = pageNode;
				break;
			default:
				BlockStackingNode blockNode = new BlockStackingNode(content, emitter, generator);
				setup(blockNode, isFirst);
				currentNode = blockNode;
				break;
		}
	}
	
	public void endContainer(IContent content, boolean finished, IContentEmitter emitter)
	{
		int type = content.getContentType( );
		switch(type)
		{
			case IContent.TABLE_BAND_CONTENT:
			case IContent.LIST_BAND_CONTENT: