[Bug]: the sp-grid renderItem callback sometimes passes undefined

[hunterloftis]

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Code of conduct

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Impacted component(s)

sp-grid

Expected behavior

If sp-grid items are all defined, renderItem is never called with an undefined value.

Actual behavior

Received a bug report that, with an Array of items where every item is defined, the renderItem callback is sometimes passed an undefined value.

Screenshots

No response

What browsers are you seeing the problem in?

No response

How can we reproduce this issue?

1. Go to '...'
2. Click on '....'
3. Scroll to '....'
4. Check console
5. See error

Sample code that illustrates the problem

This needs a minimal reproduction in order for us to write a regression test that verifies the fix moving forward.

Logs taken while reproducing problem

No response