Bug 46669 [WorkingSets] "Select/Deselect All" button for working set creation wizard.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/dialogs/ResourceWorkingSetPage.java
data.heightHint = SIZING_SELECTION_WIDGET_HEIGHT;
        data.widthHint = SIZING_SELECTION_WIDGET_WIDTH;
        tree.getControl().setLayoutData(data);
        tree.getControl().setFont(font);
        tree.addCheckStateListener(new ICheckStateListener() {
            public void checkStateChanged(CheckStateChangedEvent event) {
                handleCheckStateChange(event);
            }
        });
        tree.addTreeListener(new ITreeViewerListener() {
            public void treeCollapsed(TreeExpansionEvent event) {
            }
            public void treeExpanded(TreeExpansionEvent event) {
                final Object element = event.getElement();
                if (tree.getGrayed(element) == false)
                    BusyIndicator.showWhile(getShell().getDisplay(),
                            new Runnable() {
                                public void run() {
                                    setSubtreeChecked((IContainer) element,
                                            tree.getChecked(element), false);
                                }
                            });
            }
        });
        initializeCheckedState();
        if (workingSet != null) {
            text.setText(workingSet.getName());
        }
        setPageComplete(false);
    }