Adding linear interpolation to rgb->yuv conversion

When the UV planes are smaller than the Y plane, doing the upscaling in nearest mode was creating artefacts, so I changed it to use linear interpolation to fix the issue.

BUG=460380

Committed: https://skia.googlesource.com/skia/+/cd9d42c5167a50f1bf20e969343556d61354171b

Review URL: https://codereview.chromium.org/973563002
2 files changed