rename confusing lowp guard

Change-Id: I346429015e5f902b0a35663e140bb9a025c4220e
Reviewed-on: https://skia-review.googlesource.com/34680
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Mike Klein <mtklein@chromium.org>
diff --git a/public.bzl b/public.bzl
index d791473..dbe2d49 100644
--- a/public.bzl
+++ b/public.bzl
@@ -668,7 +668,7 @@
     # Should remove after we update golden images
     "SK_WEBP_ENCODER_USE_DEFAULT_METHOD",
     # Experiment to diagnose image diffs in Google3
-    "SK_DISABLE_SSSE3_RUNTIME_CHECK_FOR_LOWP_STAGES",
+    "SK_JUMPER_DISABLE_8BIT",
 ]
 
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