Fix sandbox target in Windows GN build and enable it.

sandbox/win/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.
 
 source_set("sandbox") {
   sources = [
     "src/acl.cc",
     "src/acl.h",
     "src/app_container.cc",
     "src/app_container.h",
@@ skipping 47 matching lines @@
     "src/policy_engine_params.h",
     "src/policy_engine_processor.cc",
     "src/policy_engine_processor.h",
     "src/policy_low_level.cc",
     "src/policy_low_level.h",
     "src/policy_params.h",
     "src/policy_target.cc",
     "src/policy_target.h",
     "src/process_mitigations.cc",
     "src/process_mitigations.h",
+    "src/process_mitigations_win32k_dispatcher.cc",
+    "src/process_mitigations_win32k_dispatcher.h",
+    "src/process_mitigations_win32k_interception.cc",
+    "src/process_mitigations_win32k_interception.h",
+    "src/process_mitigations_win32k_policy.cc",
+    "src/process_mitigations_win32k_policy.h",
     "src/process_thread_dispatcher.cc",
     "src/process_thread_dispatcher.h",
     "src/process_thread_interception.cc",
     "src/process_thread_interception.h",
     "src/process_thread_policy.cc",
     "src/process_thread_policy.h",
     "src/registry_dispatcher.cc",
     "src/registry_dispatcher.h",
     "src/registry_interception.cc",
     "src/registry_interception.h",
@@ skipping 200 matching lines @@
     "sandbox_poc/pocdll/network.cc",
     "sandbox_poc/pocdll/pocdll.cc",
     "sandbox_poc/pocdll/processes_and_threads.cc",
     "sandbox_poc/pocdll/registry.cc",
     "sandbox_poc/pocdll/spyware.cc",
     "sandbox_poc/pocdll/utils.h",
   ]
 
   defines = [ "POCDLL_EXPORTS" ]
 }