Add fuzzer test for preg_parser

components/policy/core/common/BUILD.gn

Index: components/policy/core/common/BUILD.gn
diff --git a/components/policy/core/common/BUILD.gn b/components/policy/core/common/BUILD.gn
index 17a586048824a59d4f09aaee003e300ed6eeb9d2..17217b1ad8741015d0bc8313ae8ed4612de3b605 100644
--- a/components/policy/core/common/BUILD.gn
+++ b/components/policy/core/common/BUILD.gn
@@ -3,6 +3,7 @@
 # found in the LICENSE file.
 
 import("//build/config/features.gni")
+import("//testing/libfuzzer/fuzzer_test.gni")
 
 group("common") {
   if (is_component_build) {
@@ -156,7 +157,8 @@ source_set("internal") {
       "ntdsapi.lib",
     ]
   }
-  if (is_win || is_chromeos) {
+  # Compile on Linux for fuzzer and since code is reused on Chrome OS.
+  if (is_win || is_linux) {
     sources += [
       "preg_parser.cc",
       "preg_parser.h",
@@ -296,7 +298,7 @@ source_set("unit_tests") {
     "schema_registry_unittest.cc",
     "schema_unittest.cc",
   ]
-  if (is_win || is_chromeos) {
+  if (is_win || is_linux) {
     sources += [
       "preg_parser_unittest.cc",
       "registry_dict_unittest.cc",
@@ -327,7 +329,7 @@ source_set("unit_tests") {
   if (is_mac || is_ios) {
     sources += [ "mac_util_unittest.cc" ]
   }
-  if (is_win || is_chromeos) {
+  if (is_win || is_linux) {
     # Needed by policy_loader_win_unittest.cc and preg_parser_unittest.cc
     data = [
       "//chrome/test/data/policy/",
@@ -347,3 +349,17 @@ source_set("unit_tests") {
     "//testing/gtest",
   ]
 }
+
+if (is_win || is_linux) {
+  fuzzer_test("preg_parser_fuzzer") {
+    sources = [
+      "preg_parser_fuzzer.cc",
+    ]
+    seed_corpus = "//chrome/test/data/policy/gpo/fuzzer_corpus"
+    dict = "//chrome/test/data/policy/gpo/fuzzer.dict"
+    deps = [
+      ":internal",
+      "//base",
+    ]
+  }
+}