Add fuzzer infra to blink and fuzz CSS parser

third_party/WebKit/Source/core/BUILD.gn

Index: third_party/WebKit/Source/core/BUILD.gn
diff --git a/third_party/WebKit/Source/core/BUILD.gn b/third_party/WebKit/Source/core/BUILD.gn
index a5ba3bde4eab644e2ee45a9a1785fbecb312217b..bd40405764f8308369b51e8a70b10afe5f0c26c6 100644
--- a/third_party/WebKit/Source/core/BUILD.gn
+++ b/third_party/WebKit/Source/core/BUILD.gn
@@ -1424,3 +1424,16 @@ source_set("unit_tests") {
     "//testing/gtest",
   ]
 }
+
+# Fuzzer for blink::StyleSheetContents
+fuzzer_test("stylesheet_contents_fuzzer") {
+  sources = [
+    "css/StyleSheetContentsFuzzer.cpp",
+  ]
+  deps = [
+    ":core",
+    "../platform:blink_fuzzer_test_support",
+  ]
+  seed_corpus = "//third_party/WebKit/LayoutTests/fast/css/resources"
+  libfuzzer_options = [ "max_len=2048" ]
+}