Bug 168026 Still use the existing data binding even though the aggregate is different
I had a table in which a data binding which aggregates on a group. When I insert a new data item in the report, although the expressions are same, it aggregates on All, then it refered to the existing data binding. The expected behavior would be a new data binding is created with different aggregates.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/ScalarParameterHandle.java
* 
	 * @throws SemanticException
	 * 
	 */
	public void setListlimit( int listLimit ) throws SemanticException
	{
		setIntProperty( LIST_LIMIT_PROP, listLimit );
	}
	/**
	 * get the list limited number.
	 * 
	 * @return the display prompt.
	 * 
	 */
	public int getListlimit( )
	{
		return getIntProperty( LIST_LIMIT_PROP );
	}
	/**
	 * Returns the bound columns that binds the data set columns. The item in
	 * the iterator is the corresponding <code>ComputedColumnHandle</code>.
	 * 
	 * @return a list containing the bound columns.
	 */
	public Iterator columnBindingsIterator( )
	{
		PropertyHandle propHandle = getPropertyHandle( BOUND_DATA_COLUMNS_PROP );
		return propHandle.iterator( );
	}
	/**