Eliminate unreachable code in dehydrated modules.

At present this has no effect. There isn't any dead path in the built-in
code (as you would hope) and we don't do any sufficiently-interesting
transformations that might cause unreachable code to appear.

Change-Id: I6798ae21f8721cf9f6f61ecb1765c8d8df7a9d0d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/540039
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
4 files changed