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diff --git a/gfx/angle/checkout/src/libANGLE/SizedMRUCache.h b/gfx/angle/checkout/src/libANGLE/SizedMRUCache.h
new file mode 100644
index 0000000000..b557e657ec
--- /dev/null
+++ b/gfx/angle/checkout/src/libANGLE/SizedMRUCache.h
@@ -0,0 +1,156 @@
+//
+// Copyright 2017 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// SizedMRUCache.h: A hashing map that stores blobs of sized, untyped data.
+
+#ifndef LIBANGLE_SIZED_MRU_CACHE_H_
+#define LIBANGLE_SIZED_MRU_CACHE_H_
+
+#include <anglebase/containers/mru_cache.h>
+
+namespace angle
+{
+
+template <typename Key, typename Value>
+class SizedMRUCache final : angle::NonCopyable
+{
+  public:
+    SizedMRUCache(size_t maximumTotalSize)
+        : mMaximumTotalSize(maximumTotalSize),
+          mCurrentSize(0),
+          mStore(SizedMRUCacheStore::NO_AUTO_EVICT)
+    {}
+
+    // Returns nullptr on failure.
+    const Value *put(const Key &key, Value &&value, size_t size)
+    {
+        if (size > mMaximumTotalSize)
+        {
+            return nullptr;
+        }
+
+        // Check for existing key.
+        eraseByKey(key);
+
+        auto retVal = mStore.Put(key, ValueAndSize(std::move(value), size));
+        mCurrentSize += size;
+
+        shrinkToSize(mMaximumTotalSize);
+
+        return &retVal->second.value;
+    }
+
+    bool get(const Key &key, const Value **valueOut)
+    {
+        const auto &iter = mStore.Get(key);
+        if (iter == mStore.end())
+        {
+            return false;
+        }
+        *valueOut = &iter->second.value;
+        return true;
+    }
+
+    bool getAt(size_t index, const Key **keyOut, const Value **valueOut)
+    {
+        if (index < mStore.size())
+        {
+            auto it = mStore.begin();
+            std::advance(it, index);
+            *keyOut   = &it->first;
+            *valueOut = &it->second.value;
+            return true;
+        }
+        *valueOut = nullptr;
+        return false;
+    }
+
+    bool empty() const { return mStore.empty(); }
+
+    void clear()
+    {
+        mStore.Clear();
+        mCurrentSize = 0;
+    }
+
+    void eraseByKey(const Key &key)
+    {
+        // Check for existing key.
+        auto existing = mStore.Peek(key);
+        if (existing != mStore.end())
+        {
+            mCurrentSize -= existing->second.size;
+            mStore.Erase(existing);
+        }
+    }
+
+    size_t entryCount() const { return mStore.size(); }
+
+    size_t size() const { return mCurrentSize; }
+
+    // Also discards the cache contents.
+    void resize(size_t maximumTotalSize)
+    {
+        clear();
+        mMaximumTotalSize = maximumTotalSize;
+    }
+
+    // Reduce current memory usage.
+    size_t shrinkToSize(size_t limit)
+    {
+        size_t initialSize = mCurrentSize;
+
+        while (mCurrentSize > limit)
+        {
+            ASSERT(!mStore.empty());
+            auto iter = mStore.rbegin();
+            mCurrentSize -= iter->second.size;
+            mStore.Erase(iter);
+        }
+
+        return (initialSize - mCurrentSize);
+    }
+
+    size_t maxSize() const { return mMaximumTotalSize; }
+
+  private:
+    struct ValueAndSize
+    {
+        ValueAndSize() : value(), size(0) {}
+        ValueAndSize(Value &&value, size_t size) : value(std::move(value)), size(size) {}
+        ValueAndSize(ValueAndSize &&other) : ValueAndSize() { *this = std::move(other); }
+        ValueAndSize &operator=(ValueAndSize &&other)
+        {
+            std::swap(value, other.value);
+            std::swap(size, other.size);
+            return *this;
+        }
+
+        Value value;
+        size_t size;
+    };
+
+    using SizedMRUCacheStore = base::HashingMRUCache<Key, ValueAndSize>;
+
+    size_t mMaximumTotalSize;
+    size_t mCurrentSize;
+    SizedMRUCacheStore mStore;
+};
+
+// Helper function used in a few places.
+template <typename T>
+void TrimCache(size_t maxStates, size_t gcLimit, const char *name, T *cache)
+{
+    const size_t kGarbageCollectionLimit = maxStates / 2 + gcLimit;
+
+    if (cache->size() >= kGarbageCollectionLimit)
+    {
+        WARN() << "Overflowed the " << name << " cache limit of " << (maxStates / 2)
+               << " elements, removing the least recently used to make room.";
+        cache->ShrinkToSize(maxStates / 2);
+    }
+}
+}  // namespace angle
+#endif  // LIBANGLE_SIZED_MRU_CACHE_H_