This adds a few JS tests (see *.spec.test) and runs them
using Karma and a Docker image containing Karma, node, and
Chrome (currently at 68).
We only add a Debug Test here because the Release version
has some test helpers (e.g. Region) compiled out. If those
end up not mattering for tests, we can add in a Release version.
Bug: skia:8216
Change-Id: Ica6ab3a4f21688cfa175a90d42c2254d38e8fcf1
Reviewed-on: https://skia-review.googlesource.com/145723
Reviewed-by: Joe Gregorio <jcgregorio@google.com>
Reviewed-by: Eric Boren <borenet@google.com>
