Parent-Task:

• SR-10124 String.UTF16View.distance crashes on using misaligned String.Index with native String

Issue Description:

ICU gives different character distances if we slice or don't slice the contents. Given that we will be using this distance to make a Character, this can cause us to break the invariant that Character is length 1.

ICU's next-grapheme offset for ["61", "43E", "434", "438", "64", "65", "301", "65E5", "D83E", "DDDF", "200D", "2640", "FE0F"] at 10: 13
ICU's next-grapheme offset for ["200D", "2640", "FE0F"] at 0: 1

We need to slice our content prior.