Revert "Revert "switched SkSL interpreter over to threaded code""

This reverts commit cbdc829ff126b31437d6fae5e860d182ec14a963.

Bug: skia:
Change-Id: Idb7ad413431e6556bc040369df258655c2349ef2
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/239447
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
4 files changed