Bug 150347 Support binary stream as preview image.
See 144843. We need model to save binary strame as report preview image. Currently, preview image is an external image. Maybe need a type to distinguish preview image type.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/parser/StructureState.java
{
			OdaDesignerStateStructureState state = new OdaDesignerStateStructureState(
					handler, element );
			state.setName( name );
			return state;
		}
		String propName = propDefn == null ? null : propDefn.getName( );
		if ( ( element instanceof DataSet ) )
		{
			if ( DataSet.PARAMETERS_PROP.equalsIgnoreCase( propName ) )
			{
				CompatibleDataSetParamStructureState state = new CompatibleDataSetParamStructureState(
						handler, element, propDefn, list );
				state.setName( propName );
				return state;
			}
			else if ( DataSet.COMPUTED_COLUMNS_PROP.equalsIgnoreCase( propName ) )
			{
				CompatibleComputedColumnStructureState state = new CompatibleComputedColumnStructureState(
						handler, element, propDefn, list );
				state.setName( propName );
				return state;
			}
		}
		return super.jumpTo( );
	}
	/**
	 * Creates structure instance given the structure name.
	 * 
	 * @param structDefn