Move tessellation-specific functions out of GrPathUtils

Bug: skia:12524
Change-Id: I2664c8ea707a40724bcf916e907fe28d1fa276d6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/474357
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
13 files changed