fix spelling typo

[suragch]

"empty" was spelled wrong.

• emtpy -> empty

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[LongCatIsLooong]

LGTM. But the _index field is not nullable. /cc @justinmc

[justinmc]

I guess I made several mistakes here 😊. I think this would be best actually:

// The index of the current value, or -1 if the list is empty.
int _index = -1;

Notice that in the clear method, _index gets set to -1. So this would make the state of the class consistent before the first push and after a clear.

[HansMuller]

@suragch - can you address #120062 (comment)?

[flutter-dashboard]

It looks like this pull request may not have tests. Please make sure to add tests before merging. If you need an exemption to this rule, contact Hixie on the #hackers channel in Chat (don't just cc him here, he won't see it! He's on Discord!).

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[suragch]

I've updated the PR to address the comments by @LongCatIsLooong and @justinmc

@Hixie indicated that this change doesn't need an additional test: https://discord.com/channels/608014603317936148/608021635370582020/1075853169055244359

[Hixie]

test-exempt: code refactor with no semantic change

[Renzo-Olivares]

@suragch looks like some tests are failing, though they seem unrelated to the changes in this PR. Do you mind syncing up to the latest commit and seeing if that helps?

[suragch]

@Renzo-Olivares Tests are passing after syncing.

[goderbauer]

LGTM