Bug 88838 [Undo] - API cleanup - remove IContextConsultingOperationApprover
Early on this was involved in scenarios where editors examined other operations. This is no longer used. Operation approvers generally apply to all contexts and are installed at the OperationHistory level. Until there is a concrete need for this API it should be removed. It is gratuitous at this point.
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.commands.operations.IOperationHistory#operationChanged(org.eclipse.core.commands.operations.IUndoableOperation)
	 */
	public void operationChanged(IUndoableOperation operation) {
		if (undoList.contains(operation) || redoList.contains(operation)) {
			notifyChanged(operation);
		}
	}
	
	/*
	 * Handle an exception that occurred while sending a notification about
	 * something happening in the operation history.  When notifications fail,
	 * execution should continue, but the exception should be logged.
	 */
	private void handleNotificationException(Throwable e) {
		if (e instanceof OperationCanceledException)
			return;
		
		
		if (DEBUG_OPERATION_HISTORY_UNEXPECTED) {
			System.out.print("OPERATIONHISTORY >>> Exception during notification callback ");  
			System.out.print(e);
			System.out.println();
		}
		e.printStackTrace();
	}
}