Bug 148626 [Regression]Can't fetch value from the filter of table/chart which inherites data from container
Steps: 1. create a table and bind a dataset in it 2. create another table/chart in the table detail/table group header 3. switch to the Filter tab in property editor 4. create a filter and select value in "<select value...>" combo 5. an error popuped up, "The expression value can't be retrieved"
chart/org.eclipse.birt.chart.reportitem.ui/src/org/eclipse/birt/chart/reportitem/ui/ReportDataServiceProvider.java
}
		return exps;
	}
	
		/**
	 * Gets all column bindings from handle and its container
	 * 
	 * @param itemHandle
	 *            handle
	 * @return Iterator of all bindings
	 */
	static Iterator getColumnDataBindings( ReportItemHandle itemHandle )
	{
		if ( itemHandle.getDataSet( ) != null )
		{
			return itemHandle.columnBindingsIterator( );
		}
		DesignElementHandle handle = DEUtil.getBindingHolder( itemHandle );
		if ( handle instanceof ReportItemHandle )
		{
			ArrayList list = new ArrayList( );
			Iterator i = ( (ReportItemHandle) handle ).columnBindingsIterator( );
			while ( i.hasNext( ) )
			{
				list.add( i.next( ) );
			}
			i = itemHandle.columnBindingsIterator( );
			while ( i.hasNext( ) )
			{
				list.add( i.next( ) );