Bug 156969 [regression]Group header repeat doesn't work in Web Viewer.
Description: Group header repeat doesn't work in Web Viewer. Steps to reproduce: 1. New a data source and dataset, drag the dataset to Layout. 2. Add a group. 3. Set page break in the first data item in table detail row. 4. Preview in web viewer&#12290; Expected result: Group header is repeated in each page. Actual result: No group header repeat effect.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/ir/EngineIRReader.java
{
		boolean notNull = IOUtil.readBool( in );
		if ( notNull )
		{
			DimensionType dimension = new DimensionType( );
			dimension.readObject( in );
			return dimension;
		}
		return null;
	}
	protected VisibilityDesign readVisibility( DataInputStream in )
			throws IOException
	{
		VisibilityDesign visibility = new VisibilityDesign( );
		int ruleCount = IOUtil.readInt( in );
		for ( int i = 0; i < ruleCount; i++ )
		{
			VisibilityRuleDesign rule = new VisibilityRuleDesign( );
			String format = IOUtil.readString( in );
			String expr = IOUtil.readString( in );
			rule.setFormat( format );
			rule.setExpression( expr );
			visibility.addRule( rule );
		}
		return visibility;
	}
	protected MapDesign readMap( DataInputStream in ) throws IOException
	{
		MapDesign map = new MapDesign( );
		int ruleCount = IOUtil.readInt( in );