remove templates from SkSwizzler_opts

Spin off the safer part of the SkOpts CL I had to revert.
Should we try that again, having this in place will make
it easier.

Change-Id: Ic34ce2f23c10466cf1036f9651a544d308f4edec
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/294294
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
1 file changed