There's a lot of refactoring here to fix up the
namespace of the JS (see pre/postamble js).
A reviewer can skip all the changes to interface.js,
as they are mostly whitespace changes.
Bug: skia:
Change-Id: I7cedeb98f04d4446ac4dfb555a416f30490b2b94
Reviewed-on: https://skia-review.googlesource.com/c/195885
Reviewed-by: Florin Malita <fmalita@chromium.org>
