Bug 94400 [Undo] - After successful undo, should operation be disposed by framework if it cannot be redone?
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
.toArray(new IOperationApprover[approvers.size()]);
		for (int i = 0; i < approverArray.length; i++) {
			IOperationApprover approver = approverArray[i];
			IStatus approval = approver.proceedRedoing(operation, this, info);
			if (!approval.isOK()) {
				if (DEBUG_OPERATION_HISTORY_APPROVAL) {
					System.out
							.print("OPERATIONHISTORY >>> Redo not approved by ");  
					System.out.print(approver);
					System.out.print("for operation ");  
					System.out.print(operation);
					System.out.print(approval);
					System.out.println();
				}
				return approval;
			}
		}
		return Status.OK_STATUS;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.commands.operations.IOperationHistory#getRedoHistory(org.eclipse.core.commands.operations.IUndoContext)
	 */
	public IUndoableOperation[] getRedoHistory(IUndoContext context) {
		Assert.isNotNull(context);
		return filter(redoList, context);
	}
	/*
	 * (non-Javadoc)