remove g3 flag

Bug: skia:
Change-Id: Ibe44bb816118e6bc61530c4b8d4ba83f24f72f0f
NOTRY=True
Reviewed-on: https://skia-review.googlesource.com/11322
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
diff --git a/public.bzl b/public.bzl
index 4373738..01d70f7 100644
--- a/public.bzl
+++ b/public.bzl
@@ -656,7 +656,6 @@
     # Staging flags for API changes
     # Temporarily Disable analytic AA for Google3
     "SK_NO_ANALYTIC_AA",
-    "SK_SUPPORT_LEGACY_BITMAP_SETPIXELREF",
 ]
 
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