initChannels method Null safety
protected">@protected
Sets up the method call handler for SystemChannels.restoration.
This is called by the constructor to configure the communications channel with the Flutter engine to get restoration messages.
Subclasses (especially in tests) can override this to avoid setting up that communications channel, or to set it up differently, as necessary.
Implementation
@protected
void initChannels() {
SystemChannels.restoration.setMethodCallHandler(_methodHandler);
}