[libfuzzer] Added script for dictionary generation.

content/test/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/chrome_build.gni")
 import("//build/config/compiler/compiler.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//build_overrides/v8.gni")
@@ skipping 910 matching lines @@
 }
 
 fuzzer_test("renderer_fuzzer") {
   sources = [
     "renderer_fuzzer.cc",
   ]
   deps = [
     ":test_support",
     "//content/shell:content_shell_lib",
   ]
+  dict = "data/fuzzer_dictionaries/renderer_fuzzer.dict"
 }