Don't force linear when extracting miplevel

Sorta introduced here: https://skia-review.googlesource.com/c/skia/+/338318

When we switched the controller from filter-quality to sampling, we
'continued' the old behavior of forcing bilerp when sampling a miplevel.
This matched the old enum, but the new code should respect whatever
fFilter the client has set.

Change-Id: I44bac879c1d3c880d8dbfac241e8511397de6641
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/339117
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Mike Reed <reed@google.com>
1 file changed