Executes a save request and returns success or failure.
- iOS 9.0+
- macOS 10.11+
The save request to execute.
Error information, if an error occurred.
true if the save request executes successfully; otherwise,
It is recommended that you do not access objects in the save request from other threads when it is in the process of being executed, because it may modify the contacts in the process. A save request only applies the changes to the objects. If there are overlapping changes with multiple or concurrent
CNSave then the last saved change wins.