Reland "Try to avoid vertex colors in Texture/FillRect ops when possible."

This is a reland of e0b989e5e3ab64f3585fe1bf0228e964dad0678c

Original change's description:
> Try to avoid vertex colors in Texture/FillRect ops when possible.
> 
> Avoids unnecessary fragment shader color multiplication.
> 
> Change-Id: I353d3ca91824ce20c9e9af1c5c84ab9953ddd8ab
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/201004
> Commit-Queue: Brian Salomon <bsalomon@google.com>
> Reviewed-by: Michael Ludwig <michaelludwig@google.com>

Change-Id: I22125cb7058f528cb368ff30c3c26e3d55056e66
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/201222
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
4 files changed