eliminate_dead_code in place

Not too tricky, and saves a program copy.

Change-Id: I3f7e97c1f1935df50905b6cc1ee4de33da2148ae
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/281285
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
1 file changed