Bug 213907 Provide a copy constructor for SubqueryDefinition.
Engine need a copy constructor to generate a SubqueryDefinition from an ISubqueryDefinition and change the name of the query.
data/org.eclipse.birt.report.data.adapter/src/org/eclipse/birt/report/data/adapter/impl/DataRequestSessionImpl.java
return prepare( (ICubeQueryDefinition) query,
						appContext == null
								? this.sessionContext.getAppContext( )
								: appContext );
			else
				return null;
		}
		catch ( BirtException e )
		{
			throw new AdapterException( ResourceConstants.EXCEPTION_ERROR, e );
		}
	}
	
	/*
	 * @see org.eclipse.birt.report.data.adapter.api.DataRequestSession#defineCube(org.eclipse.birt.report.model.api.olap.CubeHandle)
	 */
	public void defineCube( CubeHandle cubeDesign ) throws BirtException
	{
		if ( !cubeHandleMap.containsKey( cubeDesign.getQualifiedName( ) ) )
		{
			this.cubeHandleMap.put( cubeDesign.getQualifiedName( ), cubeDesign );
		}
	}
	
	/**
	 * 
	 * @param cubeHandle
	 * @param appContext
	 * @param stopSign
	 * @throws BirtException