There is still a bit of manual mucking about with iwyu output to get
things nice, but the checker seems to be doing ok and the process is now
a bit easier. Will see how it goes.
This also pointed out the amount of code behind ifdefs should be
minimized by using the build system and 'constexpr if' when possible.
Change-Id: Ic63fa33c65e5ff40b58858e15fc51f27d862e20d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/211349
Commit-Queue: Ben Wagner <bungeman@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
