The implementation is inconsistent across CPU and GPU.
CPU currently always implements kStrict even when kFast is passed.
For mipmapping this means computing a set of levels from the subset,
which is an expensive.
GPU limits the texture sampling coordinates to the subset in the
base level. However, higher level mipmap pixels that map back to
a footprint outside the subset are still sampled. So GPU pays a
higher shader complexity cost without really providing the benefit
of kStrict.
We are adding anisotropic filtering, which will not work well with
kStrict, and thus will also be disabled by kStrict.
Must land after https://chromium-review.googlesource.com/c/chromium/src/+/3571661
Bug: skia:10481
Bug: skia:13078
Bug: skia:13036
Canary-Chromium-CL: 3571661
Change-Id: I011b8698a3f9fafa9b819486873c8ff54df6299e
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/527284
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
072e09b26d