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diff --git a/Source/WTF/wtf/TinyLRUCache.h b/Source/WTF/wtf/TinyLRUCache.h
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+/*
+ * Copyright (C) 2010, 2016 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
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef TinyLRUCache_h
+#define TinyLRUCache_h
+
+#include <wtf/NeverDestroyed.h>
+#include <wtf/Vector.h>
+
+namespace WTF {
+
+template<typename KeyType, typename ValueType>
+struct TinyLRUCachePolicy {
+    static bool isKeyNull(const KeyType&) { return false; }
+    static ValueType createValueForNullKey() { return { }; }
+    static ValueType createValueForKey(const KeyType&) { return { }; }
+};
+
+template<typename KeyType, typename ValueType, size_t capacity = 4, typename Policy = TinyLRUCachePolicy<KeyType, ValueType>>
+class TinyLRUCache {
+public:
+    const ValueType& get(const KeyType& key)
+    {
+        if (Policy::isKeyNull(key)) {
+            static NeverDestroyed<ValueType> valueForNull = Policy::createValueForNullKey();
+            return valueForNull;
+        }
+
+        for (size_t i = 0; i < m_cache.size(); ++i) {
+            if (m_cache[i].first != key)
+                continue;
+
+            if (i == m_cache.size() - 1)
+                return m_cache[i].second;
+
+            // If the entry is not the last one, move it to the end of the cache.
+            Entry entry = WTFMove(m_cache[i]);
+            m_cache.remove(i);
+            m_cache.append(WTFMove(entry));
+            return m_cache[m_cache.size() - 1].second;
+        }
+
+        // m_cache[0] is the LRU entry, so remove it.
+        if (m_cache.size() == capacity)
+            m_cache.remove(0);
+
+        m_cache.append(std::make_pair(key, Policy::createValueForKey(key)));
+        return m_cache.last().second;
+    }
+
+private:
+    typedef std::pair<KeyType, ValueType> Entry;
+    typedef Vector<Entry, capacity> Cache;
+    Cache m_cache;
+};
+
+}
+
+using WTF::TinyLRUCache;
+using WTF::TinyLRUCachePolicy;
+
+#endif // TinyLRUCache_h