Specify DrawList as using a z test of "GREATER"
Specify DrawList as using a z test of "GREATER"

A test of GREATER, as opposed to GEQUAL, allows us to avoid double
blends during stroking.

Change-Id: I1d39b54416934ee354146fe42c58299f00f7a6e9
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/453616
Reviewed-by: Michael Ludwig <cb1f3dd24de0f0b611b26bc28bec758a551d9b7d@google.com>
Commit-Queue: Chris Dalton <ef7fc3a08ada7d31f16e9a18b5f3c728256e041e@google.com>

google/skia,google/skia,aosp-mirror/platform_external_skia,google/skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,google/skia,google/skia,aosp-mirror/platform_external_skia,google/skia,google/skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,google/skia,google/skia,google/skia,aosp-mirror/platform_external_skia