IWYU for test files starting with 'A'.

While testing some changes to iwyu, started fixing some files. Made it
to AsADashTest.cpp before running into
https://github.com/include-what-you-use/include-what-you-use/issues/364

Change-Id: I42b65df4f1f8116e0ea1b2cd774651990db1b132
Reviewed-on: https://skia-review.googlesource.com/111861
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>
7 files changed