resolve filterquality up front in imageshader

This simplifies the shader down to only 2 states:
- use the explicit SkSamplingOptions it has
- look at the paint's enum

Ultimate goal: remove the paint's enum

Middle goal: remove references/reliance on the enum downstream
in the code. This CL is partway on that.

Possible next step: retool legacy bitmapprocshader to explict work with
FilterOptions (not SkFilterQuality) -- so that eventually the enum
appears *only* when we see the paint, and can immediately turn it
into FilterOptions.

Another next-step: add SkSamplingOptions to drawImage/drawImageRect,
to make it easier to update call-sites to not rely on the paint.

Bug: skia:7650
Change-Id: Ic8e6e96af1dc74c9e1b398e7b66a4368461bf7ae
Commit-Queue: Mike Reed <>
Reviewed-by: Florin Malita <>
5 files changed