Add fuzzer for FDE CSS syntax parser.

testing/libfuzzer/BUILD.gn

 # Copyright 2016 The PDFium 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("../../pdfium.gni")
 
 config("libfuzzer_config") {
+  configs = [ "//third_party/pdfium:pdfium_core_config" ]
+
   defines = [
     "PNG_PREFIX",
     "PNG_USE_READ_MACROS",
   ]
   include_dirs = [ "../.." ]
   if (pdf_enable_v8) {
     defines += [ "PDF_ENABLE_V8" ]
   }
   if (pdf_enable_xfa) {
     defines += [ "PDF_ENABLE_XFA" ]
@@ skipping 97 matching lines @@
     ]
     deps = [
       "//third_party/pdfium:pdfium",
     ]
     configs -= [ "//build/config/compiler:chromium_code" ]
     configs += [
       "//build/config/compiler:no_chromium_code",
       ":libfuzzer_config",
     ]
   }
+  source_set("pdf_css_fuzzer") {
+    testonly = true
+    sources = [
+      "pdf_css_fuzzer.cc",
+    ]
+    deps = [
+      "//third_party/pdfium:pdfium",
+    ]
+    configs -= [ "//build/config/compiler:chromium_code" ]
+    configs += [
+      "//build/config/compiler:no_chromium_code",
+      ":libfuzzer_config",
+    ]
+  }
 }
 
 source_set("pdf_jpx_fuzzer") {
   testonly = true
   sources = [
     "pdf_jpx_fuzzer.cc",
   ]
   deps = [
     "//third_party/pdfium:pdfium",
   ]
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [
     "//build/config/compiler:no_chromium_code",
     ":libfuzzer_config",
   ]
 }