Exclude SkSL in public.bzl.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2122463002
TBR=ethannicholas
NOTREECHECKS=true

Review-Url: https://codereview.chromium.org/2122463002
diff --git a/public.bzl b/public.bzl
index 11ffa8e..9f5c9c2 100644
--- a/public.bzl
+++ b/public.bzl
@@ -128,6 +128,7 @@
 
         # Currently exclude all vulkan specific files
         "src/gpu/vk/*",
+        "src/sksl/**/*",
     ],
 )
 
@@ -423,6 +424,7 @@
         "tests/PathOpsSkpClipTest.cpp",  # Alternate main.
         "tests/skia_test.cpp",  # Old main.
         "tests/SkpSkGrTest.cpp",  # Alternate main.
+        "tests/SkSLErrorTest.cpp",  # Excluded along with Vulkan.
         "tools/gpu/gl/angle/*",
         "tools/gpu/gl/command_buffer/*",
         "tools/gpu/gl/egl/*",