When tailcalling is not supported, loop over stages.

When [[clang::musttail]] is unavailable, using tailcalls seems to be
less efficient on Android and Windows than using a conversion loop.
This CL should bring our non-tailcalling platform performance back
to previous levels.

Change-Id: I90589d0550f5a9261e946541d19c8d7f633bc29c
Bug: chromium:1504816
Bug: chromium:1504823
Reviewed-on: https://skia-review.googlesource.com/c/skcms/+/786459
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
3 files changed