Remove unreferenced canCoerce method.

Change-Id: I87cc0e6d9dc60a0ceaf32c453d2278091ea3c5e5
Bug: skia:12339
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/465393
Auto-Submit: John Stiles <johnstiles@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
2 files changed