demo/interactivity router broken

[sirreal]

This demonstrates an error where client side navigation causes an error in the interactivity-router package if server side state defining store.state.navigation as an object is removed.

Errors:

Uncaught (in promise) TypeError: Cannot set properties of undefined (setting 'hasStarted')

On this line:

// Don't update the navigation status immediately, wait 400 ms.
const loadingTimeout = setTimeout( () => {
if ( navigatingTo !== href ) {
	return;
}

if ( loadingAnimation ) {
	navigation.hasStarted = true; // <---- 💥💥💥 error
	navigation.hasFinished = false;
}
if ( screenReaderAnnouncement ) {
	a11ySpeak( 'loading' );
}
}, 400 );

Trac ticket:

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