Add Debug version of PathKit

This adds a job to build it and adds it to the npm
under /bin/debug.

The debug build is useful for clients because it
has all the debug symbols, which makes it possible to
see which WASM calls are taking the longest when using
DevTools' Performance testing.

Bug: skia:8216
Change-Id: I3068cb395f29c1de927508cf15c419f5af284eb7
Reviewed-on: https://skia-review.googlesource.com/145337
Reviewed-by: Eric Boren <borenet@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
10 files changed