Tidy DEFINE_(THREAD_SAFE_)STATIC_LOCAL() implementations.

third_party/WebKit/Source/core/loader/EmptyClients.cpp

 /*
  * Copyright (C) 2006 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009, 2012 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 29 matching lines @@
 #include "public/platform/WebApplicationCacheHost.h"
 #include "public/platform/WebMediaPlayer.h"
 #include "public/platform/modules/serviceworker/WebServiceWorkerProvider.h"
 #include "public/platform/modules/serviceworker/WebServiceWorkerProviderClient.h"
 #include "wtf/PtrUtil.h"
 #include <memory>
 
 namespace blink {
 
 void fillWithEmptyClients(Page::PageClients& pageClients) {
+  // |ChromeClient| contains a weak reference to a |Node| (which derives
+  // from |ScriptWrappable|). That reference is only used for unit testing
+  // purposes and will not accidentally leak between contexts. Consequently,
+  // disable the singleton verification check.
   DEFINE_STATIC_LOCAL(ChromeClient, dummyChromeClient,
-                      (EmptyChromeClient::create()));
+                      (EmptyChromeClient::create()), CheckScriptWrappable::No);
   pageClients.chromeClient = &dummyChromeClient;
 
   DEFINE_STATIC_LOCAL(EmptyContextMenuClient, dummyContextMenuClient, ());
   pageClients.contextMenuClient = &dummyContextMenuClient;
 
   DEFINE_STATIC_LOCAL(EmptyEditorClient, dummyEditorClient, ());
   pageClients.editorClient = &dummyEditorClient;
 
   DEFINE_STATIC_LOCAL(EmptySpellCheckerClient, dummySpellCheckerClient, ());
   pageClients.spellCheckerClient = &dummySpellCheckerClient;
@@ skipping 130 matching lines @@
 
 std::unique_ptr<WebApplicationCacheHost>
 EmptyFrameLoaderClient::createApplicationCacheHost(
     WebApplicationCacheHostClient*) {
   return nullptr;
 }
 
 EmptyRemoteFrameClient::EmptyRemoteFrameClient() = default;
 
 }  // namespace blink