Notification of disconnection from target VM.
May be caused by normal termination of a VM,
VM termination by uncaught exception or other error,
debugger action (
VirtualMachine.exit(int)) or by external events
(for example, target process termination by the
operating system, transport termination, etc).
If the target VM terminates before the disconnection, this event
will be preceded by a VMDeathEvent.