Revert "Small changes for SkText that are not in experimental directory"

This reverts commit 92f1bc0083bf2fa1d7eca2857c0d837a8dcf1f17.

Reason for revert: Blocking Android roll.

Original change's description:
> Small changes for SkText that are not in experimental directory
>
> (also made utf 8<->16 conversion static on SkUnicode)
>
> Change-Id: Ie64d18ad21a35ec10bd0b350fb7887fb78a419d8
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/448140
> Reviewed-by: Mike Reed <reed@google.com>
> Commit-Queue: Julia Lavrova <jlavrova@google.com>

Change-Id: Ieb9eb0495dddfc0f9e9e74861b24efc0201fd520
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/448656
Auto-Submit: Brian Osman <brianosman@google.com>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
5 files changed