Bug 93287 LTK Core Refactoring triggered on shutdown of JavaPlugin
org.eclipse.ltk.core.refactoring/src/org/eclipse/ltk/internal/core/refactoring/RefactoringCorePlugin.java
public static IUndoContext getUndoContext() {
		if (fRefactoringUndoContext == null) {
			fRefactoringUndoContext= new RefactoringUndoContext();
			IUndoContext workspaceContext= (IUndoContext)ResourcesPlugin.getWorkspace().getAdapter(IUndoContext.class);
			if (workspaceContext instanceof ObjectUndoContext) {
				((ObjectUndoContext)workspaceContext).addMatch(fRefactoringUndoContext);
			}
			IOperationHistory operationHistory= OperationHistoryFactory.getOperationHistory();
			operationHistory.setLimit(fRefactoringUndoContext, 5);
		}
		return fRefactoringUndoContext;
	}
	
	public static void log(IStatus status) {
		getDefault().getLog().log(status);
	}
	
	public static void log(Throwable t) {
		IStatus status= new Status(
			IStatus.ERROR, getPluginId(), 
			IRefactoringCoreStatusCodes.INTERNAL_ERROR, 
			RefactoringCoreMessages.RefactoringCorePlugin_internal_error,  
			t);
		ResourcesPlugin.getPlugin().getLog().log(status);
	}
	
	public static void logRemovedListener(Throwable t) {
		IStatus status= new Status(
			IStatus.ERROR, getPluginId(), 
			IRefactoringCoreStatusCodes.INTERNAL_ERROR,