Migrate caps-bit lookup code from IRGenerator to Setting.

This CL moves existing code from point A to point B; the logic should be
the same as before.

Change-Id: I90c39588531a34f74c4b1802a7c692c08ddc4f16
Bug: skia:11365
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/375075
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
4 files changed