Handle new sRGBA SkColorType

Guarded so that we can land:
  https://skia-review.googlesource.com/c/skia/+/438219

Change-Id: If1392e8ca24669dd6157e8de57986f056aef2b1d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3115125


Reviewed-by: vmpstr <vmpstr@chromium.org>
Commit-Queue: Brian Osman <brianosman@google.com>
Cr-Commit-Position: refs/heads/main@{#914516}