Bug 181706 Sorting Data by X values doesn't work without grouping
Using the 2.2M5 designer , I simply want to sort the data of the X Series in a Line Chart. I go into the Sort and Group pop up in the chart wizard and select ascending, but it doesn't affect the result. (style ordered same as the result set) If i define a dummy grouping (no interval) it is then working.
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/internal/datafeed/DataProcessor.java
if ( expr != null
								&& expr.trim( ).length( ) > 0
								&& !rt.contains( expr ) )
						{
							rt.add( expr );
						}
					}
				}
			}
		}
		if ( rt.size( ) > 0 )
		{
			return (String[]) rt.toArray( new String[rt.size( )] );
		}
		return null;
	}
	private GroupKey[] findGroupKeys( Chart cm, GroupingLookupHelper lhmLookup )
	{
		if ( cm instanceof ChartWithAxes )
		{
			return findGroupKeys( (ChartWithAxes) cm, lhmLookup );
		}
		else if ( cm instanceof ChartWithoutAxes )
		{
			return findGroupKeys( (ChartWithoutAxes) cm, lhmLookup );
		}
		return null;
	}
	private GroupKey[] findGroupKeys( ChartWithoutAxes cwoa,
			GroupingLookupHelper lhmLookup )