Bug 212497 Need api to get all referencable report item with cube
Need model provide new api to return all referencable report items for dataset or cube respectively. For instance: getAvailableDataSetBindingReferenceList(); getAvailableCubeBindingReferenceList(); also keep current api: getAvailableDataBindingReferenceList().
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/ReportItemHandle.java
if ( name == null )
			return null;
		List columns = (List) getProperty( BOUND_DATA_COLUMNS_PROP );
		if ( columns == null )
			return null;
		for ( int i = 0; i < columns.size( ); i++ )
		{
			ComputedColumn column = (ComputedColumn) columns.get( i );
			if ( name.equals( column.getName( ) ) )
				return (ComputedColumnHandle) column.handle(
						getPropertyHandle( BOUND_DATA_COLUMNS_PROP ), i );
		}
		return null;
	}
	/**
	 * Removes unused bound columns from the element. Bound columns of nested
	 * elements will not be removed. For example, if calls this method for a
	 * list thaat contains a text-data, unused bound columns on list are
	 * removed. While, unused columns on text-data still are kept.
	 * 
	 * @throws SemanticException
	 *             if bound column property is locked.
	 */
	public void removedUnusedColumnBindings( ) throws SemanticException
	{
		UnusedBoundColumnsMgr.removedUnusedBoundColumns( this );
	}
	/**
	 * Gets TOC handle.
	 *