KeepAliveNotification constructor
Creates a notification to indicate that a subtree must be kept alive.
The handle
must not be null.
Implementation
const KeepAliveNotification(this.handle) : assert(handle != null);
Creates a notification to indicate that a subtree must be kept alive.
The handle
must not be null.
const KeepAliveNotification(this.handle) : assert(handle != null);