fix for SkSL lexer crash on non-ASCII input

Bug: skia:7126
Change-Id: Ic884d14daf91fd668afe9e29d2f82d1ef1089cce
Reviewed-on: https://skia-review.googlesource.com/56720
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index 14ce04a..2b333af 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -429,6 +429,9 @@
 
   action("run_sksllex") {
     script = "gn/run_sksllex.py"
+    deps = [
+      ":sksllex(//gn/toolchain:$host_toolchain)",
+    ]
     sources = [
       "src/sksl/lex/layout.lex",
       "src/sksl/lex/sksl.lex",