Bug 312959 [Import/Export] importing file from big disk hangs UI
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/dialogs/ResourceTreeAndListGroup.java
BusyIndicator.showWhile(treeViewer.getControl().getDisplay(),
                    new Runnable() {
                        public void run() {
                            setListForWhiteSelection(treeElement);
                            listViewer.setAllChecked(true);
                        }
                    });
        } else {
            List listItemsToCheck = (List) checkedStateStore.get(treeElement);
            if (listItemsToCheck != null) {
                Iterator listItemsEnum = listItemsToCheck.iterator();
                while (listItemsEnum.hasNext()) {
					listViewer.setChecked(listItemsEnum.next(), true);
				}
            }
        }
    }
    /**
     *	Logically gray-check all ancestors of treeItem by ensuring that they
     *	appear in the checked table. Add any elements to the selectedNodes
     *  so we can track that has been done.
     */
    private void primeHierarchyForSelection(Object item, Set selectedNodes) {
        
        if (selectedNodes.contains(item)) {
			return;
		}
        checkedStateStore.put(item, new ArrayList());
        
        expandedTreeNodes.add(item);