Remove support for non-AA in the tessellation atlas

Now that multisampleDisableSupport is completely turned off, this
won't change any behavior.

Change-Id: I3fe0518aee5321c7c92ac0b4b77333e910f08ce6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/431076
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
5 files changed