Many things are not enabled currently (e.g. Skottie, Paragraph),
but we can render many APIs using WebGL.
To turn on Paragraph, etc, we'll need to tackle fonts, which
is a separate effort.
This also changes where the build artifacts go. ./build/ is
easier to deal with than the old way of sticking them in
./npm_build/bin
Change-Id: Ia377360af580a887d03630670438fea2e3157e90
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/470682
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>
ef3d6af042