Remove SharedBuffer::unlock() and keep Resource's SharedBuffer always locked

third_party/WebKit/Source/core/fetch/FontResource.h

 /*
  * Copyright (C) 2007, 2008 Apple Inc. 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.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 61 matching lines @@
         {
             return new FontResource(request, options);
         }
     };
     FontResource(const ResourceRequest&, const ResourceLoaderOptions&);
 
     void checkNotify() override;
     void fontLoadShortLimitCallback(TimerBase*);
     void fontLoadLongLimitCallback(TimerBase*);
 
-    bool isSafeToUnlock() const override;
-
     enum LoadLimitState { UnderLimit, ShortLimitExceeded, LongLimitExceeded };
 
     std::unique_ptr<FontCustomPlatformData> m_fontData;
     String m_otsParsingMessage;
     LoadLimitState m_loadLimitState;
     bool m_corsFailed;
     Timer<FontResource> m_fontLoadShortLimitTimer;
     Timer<FontResource> m_fontLoadLongLimitTimer;
 
     friend class MemoryCache;
 };
 
 DEFINE_RESOURCE_TYPE_CASTS(Font);
 
 class FontResourceClient : public GarbageCollectedMixin, public ResourceClient {
 public:
     ~FontResourceClient() override {}
     static bool isExpectedType(ResourceClient* client) { return client->getResourceClientType() == FontType; }
     ResourceClientType getResourceClientType() const final { return FontType; }
     virtual void fontLoadShortLimitExceeded(FontResource*) {}
     virtual void fontLoadLongLimitExceeded(FontResource*) {}
 
     DEFINE_INLINE_VIRTUAL_TRACE() {}
 };
 
 } // namespace blink
 
 #endif