Bug 65268 [projection] editor is missing collapse all action for code folding
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/actions/FoldingActionGroup.java
fCollapse= null;
			fExpandAll= null;
			fRestoreDefaults= null;
			fCollapseMembers= null;
			fCollapseComments= null;
			fProjectionListener= null;
			return;
		}
		
		fViewer= (ProjectionViewer) viewer;
		
		fProjectionListener= new IProjectionListener() {
			public void projectionEnabled() {
				update();
			}
			public void projectionDisabled() {
				update();
			}
		};
		
		fViewer.addProjectionListener(fProjectionListener);
		
		fToggle= new PreferenceAction(FoldingMessages.getResourceBundle(), "Projection.Toggle.", IAction.AS_CHECK_BOX) { 
			public void run() {
				IPreferenceStore store= JavaPlugin.getDefault().getPreferenceStore();
				boolean current= store.getBoolean(PreferenceConstants.EDITOR_FOLDING_ENABLED);
				store.setValue(PreferenceConstants.EDITOR_FOLDING_ENABLED, !current);
			}
			public void update() {
				ITextOperationTarget target= (ITextOperationTarget) editor.getAdapter(ITextOperationTarget.class);