Revert "Add sRGB 8888 colortype"

This reverts commit 0f7c10ef5681d5c739bcd8862c58d856fd663a0c.

Reason for revert: Unhappy rollers

Original change's description:
> Add sRGB 8888 colortype
>
> A color type that linearizes just after loading, and re-encodes to sRGB
> just before storing, mimicking the GPU formats that work the same way.
>
> Notes:
>   - No mipmap support
>   - No SkPngEncoder support (HashAndEncode's .pngs are ok, though?)
>   - Needs better testing
>
> This is a re-creation of reviews.skia.org/392990
>
> Change-Id: I4739c2280211e7176aae98ba0a8476a7fe5efa72
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/438219
> Commit-Queue: Brian Osman <brianosman@google.com>
> Reviewed-by: Brian Salomon <bsalomon@google.com>

TBR=bsalomon@google.com,robertphillips@google.com,brianosman@google.com,reed@google.com,skcq-be@skia-corp.google.com.iam.gserviceaccount.com

Change-Id: Ie199535b9b65ec7c7fef3c773452ea06bdbd2d9c
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/441376
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
32 files changed