Remove Switch support from DSL entirely.

This isn't used anywhere; it's just dead code.

Change-Id: I2617e94faf088da67bb7d44aea5399485b6a3938
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/694437
Auto-Submit: John Stiles <johnstiles@google.com>
Commit-Queue: Arman Uguray <armansito@google.com>
Reviewed-by: Arman Uguray <armansito@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
9 files changed