[skottie] Use SkShaper for text

Update the text adapter to shape using SkShaper.

Bug: skia:
Change-Id: Ie6ea579a1f58b2f6ba6101dcdfad8ae9809de808
Reviewed-on: https://skia-review.googlesource.com/c/183387
Commit-Queue: Florin Malita <fmalita@chromium.org>
Reviewed-by: Mike Reed <reed@google.com>