Remove unused pageSize from enableLoadMore

[matthewrfennell]

Description

Pagination offset (by which I mean the distance from the top message before we start loading more) used to be determined by the offset parameter passed to enableLoadMore, like so:

if ids.prefix(offset + 1).contains(message.id) {
    onEvent?(message)
}

This got changed in 568d00d. Now, we rely on paginationTargetIndexPath instead, which is hardcoded to be the last already loaded message:

IndexPath(row: lastSection.rows.count - 1, section: sections.count - 1)

As a result, pageSize is no longer used. Remove it to make sure that consumers do not expect different behaviour when they modify the parameter.

Comments

I was tempted to re-add that offset functionality, but this comment made me pause:

/// call pagination handler when this row is reached
/// without this there is a bug: during new cells insertion willDisplay is called one extra time for the cell which used to be the last one while it is being updated (its position in group is changed from first to middle)

I didn't quite understand it, is it saying that we don't want to call the pagination handler at all before we reach the last already loaded message?

Anyway, if you'd like me to look at adding that functionality back, I'd be more than happy to take a look, just didn't want to start making changes without understanding the history first :)

[f3dm76]

Hey @matthewrfennell, this comment just means that we should store the target index, and can't rely on easy math on the fly, because of some swiftUI shenanigans. I think it's better to restore trigger offset functionality if at all possible, it will help preserve the API if nothing else. If you're willing to work on that, please remember to test the initial calling of pagination when there are <= paginationThresholdValue cells in the table (including zero). But if you think that just using the last cell is ok in most cases, I can merge this PR. Have a fantastic day!