[canvaskit] Include WebP and JPEG encoding in npm version

Change-Id: I3086129d6fd7e3505a93bf8157b55ad2c5096902
Bug: skia:12853
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/500376
Reviewed-by: Nathaniel Nifong <nifong@google.com>
4 files changed