Strip out unused tracing macros

Bug: skia:
Change-Id: I3edbc50820af6414405a7d4810178e050234db0c
Reviewed-on: https://skia-review.googlesource.com/24743
Reviewed-by: Mike Klein <mtklein@chromium.org>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
1 file changed