Bug 151694 appContext is null when evaluating parameters
On a report with parameters, during the resolution of the report parameters, datasource used to populate values of each parameters doesn't have any appContext. We used a jdbcbridbe, and thru appContext, we're retrieving jndi name and others parameters usueful for our datasource. In those case, during the evaluation of parameters, appContext is null so the datasource used to populate values of the parameters are not from the same database ...
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/GetParameterDefinitionTask.java
}
					Object value = iter.getValue( valueColumnName );
					choices.add( new SelectionChoice( label, convertToType(
							value, dataType ) ) );
					count++;
					if ( ( limit != 0 ) && ( count >= limit ) )
					{
						break;
					}
					iter.skipToEnd( 1 ); 
				}
			}
			catch ( BirtException ex )
			{
				ex.printStackTrace( );
			}
		}
		if ( !fixedOrder )
			Collections.sort( choices, new SelectionChoiceComparator( true, pattern, ULocale.forLocale( locale ) ) );
		return choices;
	}
	/**
	 * The first step to work with the cascading parameters. Create the query
	 * definition, prepare and execute the query. Cache the iterator of the
	 * result set and also cache the IBaseExpression used in the prepare.
	 * 
	 * @param parameterGroupName -
	 *            the cascading parameter group name
	 */
	public void evaluateQuery( String parameterGroupName )