Revert "Assert that all GrCaps colortype/format -> swizzle queries are legal."

This reverts commit aa8bf26dc257f0f94f6eea5aedce2923cc603f07.

Reason for revert: d3d9 failures

Original change's description:
> Assert that all GrCaps colortype/format -> swizzle queries are legal.
> 
> Otherwise they silently fall back to "rgba".
> 
> Change-Id: I9a4dcfc99ae52f156b6dfc367665eb0129b6b03d
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/280336
> Reviewed-by: Chris Dalton <csmartdalton@google.com>
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Commit-Queue: Brian Salomon <bsalomon@google.com>

TBR=egdaniel@google.com,bsalomon@google.com,csmartdalton@google.com

Change-Id: I05940da3ae6d93e7a0b44790b8051ce3221e62d7
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/280403
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
6 files changed