Bug 88352 Operation supports leaks contexts via action handler
I20050315-1100 Susan, this is a different leak from the one that I reported. Test Case: 1. open text editor 2. close text editor ==> DefaultUndoManager is leaked due to undo/redo actions handlers still holding on to the context.
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/IOperationHistory.java
*             if an exception occurred during redo.
	 */
	IStatus redoOperation(IUndoableOperation operation,
			IProgressMonitor monitor, IAdaptable info)
			throws ExecutionException;
	/**
	 * Remove the specified operation from the history. Listeners will be
	 * notified of the removal of the operation. This method is used by clients
	 * who want to flush a particular subset of the history.
	 * 
	 * @param operation -
	 *            the operation to be removed from the history
	 */
	void remove(IUndoableOperation operation);
	/**
	 * Remove the specified operation approver from the operation history.
	 * 
	 * @param approver -
	 *            the IOperationApprover to be removed
	 */
	void removeOperationApprover(IOperationApprover approver);
	/**
	 * Remove the specified listener from the operation history.
	 * 
	 * @param listener -
	 *            The IOperationHistoryListener to be removed
	 */
	void removeOperationHistoryListener(IOperationHistoryListener listener);
	/**
	 * Set the limit on the undo and redo history for a particular context.