Eliminate empty statements/nops in dehydrated modules.

This doesn't improve the quality of final code, so we can skip this pass
during normal program compilation, but there's no excuse for leaving
Nops in a dehydrated module that we always load into memory at startup.

Change-Id: I7ff94f2713cff658799c469a46b526544dfc318c
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/540040
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Arman Uguray <armansito@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
7 files changed