Migrate unreachable-code elimination to Analysis.

Change-Id: Ib0c79046044f159b35f0cbaf06c7931c37a09ac4
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/451299
Auto-Submit: John Stiles <johnstiles@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
3 files changed