Bug 258810 [Markers] Markers for the entire workspace show up when working set empty
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/views/markers/MarkerContentGenerator.java
* @param subMonitor
	 * @return MarkerEntry
	 */
	private Collection computeAllMarkers(SubProgressMonitor subMonitor) {
		Collection allMarkers = new HashSet();
		findMarkers(allMarkers, new IResource[] { ResourcesPlugin
				.getWorkspace().getRoot() }, null, IResource.DEPTH_INFINITE,
				subMonitor);
		return allMarkers;
	}
	/**
	 * Compute the marker for the supplied filter and add to return markers.
	 * 
	 * @param returnMarkers
	 *            {@link Collection} of {@link IMarker}
	 * @param subMonitor
	 * @param filterGroup
	 * @param focusResources
	 *            the resource currently selected
	 */
	private void computeMarkers(Collection returnMarkers,
			SubProgressMonitor subMonitor, MarkerFieldFilterGroup filterGroup,
			IResource[] focusResources) {
		int filterType = filterGroup.getScope();
		
		filterGroup.refresh(); 
		
		switch (filterType) {
		case MarkerFieldFilterGroup.ON_ANY: {
			findMarkers(returnMarkers, new IResource[] { ResourcesPlugin