Move SkTileModes to top level

- move shader factories to their host (e.g. picture->makeShader)

More to do to formally deprecated SkShader::TileMode

Bug: skia:8937
Change-Id: I101e42fb9fba4ab91d028a34888f1fde16fdece4
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/205589
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Mike Reed <reed@google.com>
Auto-Submit: Mike Reed <reed@google.com>
20 files changed