Unliking a post updates like count on front end

[NimaBoscarino]

Fixes the issue outlined by #9638.

Previous behaviour:

New behaviour:

[Gargron]

I'm sorry, but there is a reason why an asynchronous worker is used. Yes, your code returns the real state, but does so by running a lot of tasks (including networking) within the request/response cycle. If connection drops in the middle, the unfavourite operation could miss some instructions. It would be far easier to update the favourites count in the Redux reducer on the client-side.

[NimaBoscarino]

Thanks for the feedback! I'll undo the changes that I made, and I'll do it on the Redux reducer side instead.

[NimaBoscarino]

Okay, I did it through the reducer on the client-side! Does this look better?

[Gargron]

A more concise way of writing this is:

return state.updateIn([action.status.get('id'), 'favourites_count'], x => Math.max(x - 1, 0));