Revert "Revert "Simplify SkTypeface::charsToGlyphs API to require UTF32 input""

with legacy guard for google3

Needs this to land first: https://critique.corp.google.com/#review/243924283

This reverts commit 70ed05e53ad244b3234415b447e5fcd53fb40e3b.

Change-Id: I3e821dfcdbf3004382092338ebad7cceaf40cefd
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/208668
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
Auto-Submit: Mike Reed <reed@google.com>
27 files changed