Skia now supports explicit controls over the sampling technique:
- filtering: nearest, linear, cubic (only works with mipmaps:none)
- mipmaps: none, nearest, linear (allows trilerp)

See SkSamplingOptions.h

Switching to these means skia no longer "changes" the technique based on
heuristics (like the direction of the scaling): you always get what you
ask for (more predictable).

Need to rebaseline tests, as sometimes (e.g.) Skia used to treat
"High Qualitty" (ala bicubic) as just bilinear when downscaling.

The SkFilterQuality enum is deprecated: it is mapped as follows:

kNone.  : [ filter:nearest, mipmap:none    ]
kLow    : [ filter:linear,  mipmap:none    ]
kMedium : [ filter:linear,  mipmap:nearest ]
kHigh   : [ filter:cubic,   mipmap:none    ]

You can now specify these directly when you create an ImageShader.
Specifying the enum in SkPaint is depcrecated, and will be removed.

Bug: skia:7650
Change-Id: I5251b195fbc8ff7e71d3aa76fdc3dde139a35c0c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2562751
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Florin Malita <fmalita@chromium.org>
Reviewed-by: Jonathan Backer <backer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#832543}