Don't drop mip map mode in GrTextureOp->GrTextureEffect fallback

Change-Id: I900345ba52605c3b3e0f077655ec5c25bab01b9c
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/337721
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
1 file changed