Use mixed samples in GrDynamicAtlas

Change-Id: I0871f2e87be857ebf8577b212b318054a2ad84dd
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/269908
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
1 file changed