Dense zero trie Out of Range handling #7303

[Cdog1526]

Working on https://github.com/unicode-org/icu4x/issues/7303.

When creating a dense sparse zerotrie, if the incoming values are too spread out for a dense matrix:

• Select the row offset that gets the greatest number of values into the dense matrix.
• Put all out-of-range values into the primary trie, as we do with sparse rows.

Also, added a test case for this. I am not certain that this test case is sufficient, this is my first contribution here.

[CLAassistant]

All committers have signed the CLA.

[Cdog1526]

@sffc I see that two tests are failing right now, but I'm not really sure how to recreate that on my side - is there something I can run or look at or is this related to me? And is there anything else I should do?

[sffc]

The branch might be stale. I updated it to main

[Cdog1526]

Ah awesome, thanks! Let me know if you need anything else to review.