Update Builder to support binary-ops generically.

This will let us add binary ops without a ton of boilerplate for
each one.

Change-Id: I910113019428a65e59084b3accaa899a4f752ec0
Bug: skia:13676
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/611376
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
4 files changed