Bug 203838 [Markers] [Markers] clicking on column headers does not sort table
I20070918 Clicking on any of the column headers does not sort based on the relevant column.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/provisional/views/markers/MarkerContentGenerator.java
returnMarkers = new HashSet(matching);
					else
						findIntersection(matching, returnMarkers);
					matching.clear();
				}
				
			} else {
				returnMarkers = new HashSet();
				while (filtersIterator.hasNext()) {
					computeMarkers(returnMarkers, subMonitor,
							(MarkerFieldFilterGroup) filtersIterator.next());
				}
			}
		} else
			returnMarkers = computeAllMarkers(subMonitor);
		MarkerEntry[] entries = new MarkerEntry[returnMarkers.size()];
		Iterator markers = returnMarkers.iterator();
		int index = 0;
		
		while(markers.hasNext()){
			entries[index] = new MarkerEntry((IMarker) markers.next());
			index ++;
		}
		
		return new MarkerMap(entries);
	}
	/**
	 * Iterate through the return markers. If they do not exist in matching remove them.
	 * @param matching
	 * @param returnMarkers