Revert "gbr- has been brg- this whole time..."

This reverts commit 5b9a037bf41591e0076843f619ee47c9ad30e42d.

Reason for revert: 

I got confused in here somewhere and everything is drawing wrong.

Original change's description:
> gbr- has been brg- this whole time...
> 
> Rewrite things to make that a little clearer.
> 
> A red pixel ends up in channel 2, what would naively draw as blue
> without a rotation.  A green pixel ends up in channel 0, which would
> naively draw as red without rotation.  A blue pixel ends up in channel
> 1, which would naively draw as green without this rotation.
> 
> So this transformation is:
> 
>    r -> b
>    g -> r
>    b -> g
> 
> i.e. rgb_to_brg
> 
> Change-Id: I12331ff2622194e34a44f421f656fbe4db5d3dca
> Reviewed-on: https://skia-review.googlesource.com/65521
> Commit-Queue: Brian Osman <brianosman@google.com>
> Reviewed-by: Brian Osman <brianosman@google.com>

TBR=mtklein@chromium.org,brianosman@google.com

Change-Id: Ib29800b242bf736b20d61375d3c437c8f4ffdce0
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/65781
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Mike Klein <mtklein@chromium.org>
13 files changed