Bug 114542 [Markers] Possible to get empty path nodes in problems view hierarcahl mode
20051101 Warnings on the top level of a project ended up having an empty label. STEPS 1) Change filters to show selected elements and children 2) Go into hierarchal mode 3) Select org.eclipse.ui.tests
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/views/markers/internal/MarkerView.java
updateJob.refresh(changed);
					getProgressService().schedule(updateJob);
				}
			}
			if (addRefreshRequired(addedMarkers) || removeRefreshRequired(removedMarkers)) {
				updateJob.refreshAll();
				getProgressService().schedule(updateJob);
			}
		}
		/**
		 * Return whether or not any of the removedMarkers are being 
		 * shown.
		 * @param removedMarkers
		 * @return <code>boolean</code>
		 */
		private boolean removeRefreshRequired(Collection removedMarkers) {
			if(removedMarkers.isEmpty())
				return false;
			
			MarkerList currentList = getCurrentMarkers();
			Iterator removes = removedMarkers.iterator();
			while(removes.hasNext()){
				if(currentList.getMarker((IMarker) removes.next())!= null)
					return true;
			}
			
			return false;
		}
		/**
		 * Preprocess to see if an update is required.