Update getNavigationBadge method to allow Closures

[caendesilva]

Description

This allows badges to use dynamic or deferred data. Since the actual NavigationItem::badge method supports this I think it makes sense.

Visual changes

None

Functional changes

• Code style has been fixed by running the composer cs command.
• Changes have been tested to not break existing functionality.
• Documentation is up-to-date.

[danharrin]

I think a better solution would be to swap static::getNavigationBadge() with static::getNavigationBadge(...) so it gets run on demand as a Closure instead of called once? Then people don't need to change how the badge gets returned

Also, does this impact how many times the badge method is run per request, do we need to cache the result?

[danharrin]

Closing as my proposed solution is a rewrite anyway

[caendesilva]

Closing as my proposed solution is a rewrite anyway

Cool! Yeah this was more of a proof of concept to see if it's a good fit. I actually ended up going with your on demand closure route in my application when implementing a workaround yesterday.