Bug 136270 Group's data binding column can only be used by the group itself
If you add some data binding columns to a group, these columns can only be used by this group itself. It should has a way to make the child can use the parent group's data binding column.
UI/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/util/DEUtil.java
}
	private static int getLargerFontSizeIntValue( DesignElementHandle handle )
	{
		if ( !( handle instanceof ReportItemHandle ) )
		{
			if ( handle instanceof ModuleHandle )
			{
				
				String size = (String) DesignerConstants.fontMap.get( DesignChoiceConstants.FONT_SIZE_MEDIUM );
				return Integer.parseInt( size ) + 1;
			}
			if ( handle instanceof GroupHandle )
			{
				handle = handle.getContainer( );
			}
		}
		Object fontSizeValue = getModelFontSize( handle );
		if ( fontSizeValue instanceof DimensionValue )
		{
			int size = getFontSizeIntValue( handle.getContainer( ) );
			return (int) CSSUtil.convertToPoint( fontSizeValue, size ) + 1;
		}
		else if ( fontSizeValue instanceof String )
		{
			String fontSize = (String) fontSizeValue;
			if ( fontSize.equals( DesignChoiceConstants.FONT_SIZE_LARGER ) )
			{
				return getLargerFontSizeIntValue( handle.getContainer( ) );
			}
			else if ( fontSize.equals( DesignChoiceConstants.FONT_SIZE_SMALLER ) )