IWYU for some test files starting with 'C'.

Change-Id: Iea274ae52da8b4b87ec55222c856f40a0d88c4e0
Reviewed-on: https://skia-review.googlesource.com/113746
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>
Reviewed-on: https://skia-review.googlesource.com/113944
Reviewed-by: Ben Wagner <bungeman@google.com>
16 files changed