Revert "use colorspace steps to determine legacy blits"

This reverts commit 09198525261aa5152c2183158315d81176776d99.

Reason for revert: speculative: unblock android roll

Original change's description:
> use colorspace steps to determine legacy blits
> 
> Bug: skia:8793
> Change-Id: I1de4bde25f7dcb12175733a3213c43f92410dc4a
> Reviewed-on: https://skia-review.googlesource.com/c/196647
> Commit-Queue: Mike Reed <reed@google.com>
> Reviewed-by: Mike Klein <mtklein@google.com>
> Reviewed-by: Brian Osman <brianosman@google.com>

TBR=mtklein@google.com,brianosman@google.com,reed@google.com

Change-Id: I79a21df9a3c3a9f3127f57131feff0f3e417e642
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:8793
Reviewed-on: https://skia-review.googlesource.com/c/196774
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
3 files changed