delete SkLayer.cpp

Change-Id: I7c0325daef62948ea9f5ef58a06236be502f3ef7
Reviewed-on: https://skia-review.googlesource.com/7783
Commit-Queue: Hal Canary <halcanary@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>
2 files changed