remove stray SkTLList includes

Change-Id: I63ba2424bd70f53c14d15bb332a585881d2c4613
Reviewed-on: https://skia-review.googlesource.com/135451
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Mike Klein <mtklein@chromium.org>
4 files changed