Clarify behavior for setting a badge to flag when a number is already showing

[marcoscaceres]

As in:

await navigator.setAppBadge(2);
// System doesn't support flag 
await navigator.setAppBadge();

What should happen?

WebKit opinion: it should keep the number.

[fallaciousreasoning]

Hmmmm I'm not sure what the most sensible behavior would be. I guess we have three options:

1. Completely ignore the call (keeping the number)
2. Clear the badge
3. Set the badge to 1 or some supported number.

I think 2 is my least favorite option. The more I think about 1 the more I like it, but I wonder if there's anyone else it'd be good to ask

[marcoscaceres]

none of the solutions are great, to be honest... but, at least, it's the above situation is extremely rare, and maybe we should discourage setting just the badge: setting the badge implies some call to action... which is "1". And on platforms where no number is shown, you will get a un-numbered badge regardless.

the developer has no way of knowing what the OS will show, so it's always safest and most cross-platform to always use a number.

[marcoscaceres]

Also, for developers who explicitly want to set the badge to a non-number:

await navigator.setAppBadge(2);

// something happens...
await navigator.clearAppBadge();

// Explicitly set it to just a circle for whatever reason.
await navigator.setAppBadge();