SkSL: Remove ByteCode interpreter, generator, etc.

Change-Id: Ib150e6d6d3de34a85ce8051eea843ab3b2d7ab75
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/356921
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
19 files changed