Bug 132515 Expression like "Toltal.rank(Tolta.ave(row[a]),ture,Null,1)" is return an error
Description: Add an expression like "Toltal.rank(Tolta.ave(row[a]),ture,Null,1)" is return an error.The nesting "Toltal" seem not to be work. Step to reproduce: 1.new a datasource and dataset 2.drag the dataset to layout veiw for a table 3.set a group on the table 4.Insert a data into the group header with the expression e.g. "Toltal.rank(Tolta.ave(row[a]),ture,Null,1)" Actual result: An error was thrown out Expected result: It should work correctly in order to support some requirments
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/expression/ExpressionProcessor.java
helper.setQuery( query );
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.data.engine.executor.IExpressionProcessor#getScope()
	 */
	public Scriptable getScope( )
	{
		return this.dataSet.getScriptScope();
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.data.engine.executor.IExpressionProcessor#compile(org.eclipse.birt.data.engine.executor.IComputedColumnState)
	 */
	public void compileComputedColumn( IComputedColumnsState computedColumns )
	{
		assert ( computedColumns != null );
		this.computedColumnState = computedColumns;
		
		IScriptExpression cmptdColumn = null;
		String name = "",expression="";
		Context context = Context.enter();
		try
		{
			for ( int i = 0; i < computedColumnState.getCount( ); i++ )
			{