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
import org.eclipse.jface.text.source.projection.ProjectionViewer;
import org.eclipse.ui.actions.ActionGroup;
import org.eclipse.ui.texteditor.ITextEditor;
import org.eclipse.ui.texteditor.IUpdate;
import org.eclipse.ui.texteditor.ResourceAction;
import org.eclipse.ui.texteditor.TextOperationAction;
import org.eclipse.ui.editors.text.IFoldingCommandIds;
import org.eclipse.jdt.ui.PreferenceConstants;
import org.eclipse.jdt.ui.actions.IJavaEditorActionDefinitionIds;
import org.eclipse.jdt.internal.ui.JavaPlugin;
import org.eclipse.jdt.internal.ui.javaeditor.JavaEditor;
/**
 * Groups the JDT folding actions.
 *  
 * @since 3.0
 */
public class FoldingActionGroup extends ActionGroup {
	private static abstract class PreferenceAction extends ResourceAction implements IUpdate {
		PreferenceAction(ResourceBundle bundle, String prefix, int style) {
			super(bundle, prefix, style);
		}
	}
	
	/**
	 * @since 3.2
	 */
	private class FoldingAction extends PreferenceAction {
		FoldingAction(ResourceBundle bundle, String prefix) {
			super(bundle, prefix, IAction.AS_PUSH_BUTTON);
		}