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diff --git a/gfx/angle/checkout/src/common/CircularBuffer.h b/gfx/angle/checkout/src/common/CircularBuffer.h
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+++ b/gfx/angle/checkout/src/common/CircularBuffer.h
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+//
+// Copyright 2021 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.
+//
+// CircularBuffer.h:
+//   An array class with an index that loops through the elements.
+//
+
+#ifndef COMMON_CIRCULARBUFFER_H_
+#define COMMON_CIRCULARBUFFER_H_
+
+#include "common/debug.h"
+
+#include <algorithm>
+#include <array>
+
+namespace angle
+{
+template <class T, size_t N, class Storage = std::array<T, N>>
+class CircularBuffer final
+{
+  public:
+    using value_type      = typename Storage::value_type;
+    using size_type       = typename Storage::size_type;
+    using reference       = typename Storage::reference;
+    using const_reference = typename Storage::const_reference;
+    using pointer         = typename Storage::pointer;
+    using const_pointer   = typename Storage::const_pointer;
+    using iterator        = typename Storage::iterator;
+    using const_iterator  = typename Storage::const_iterator;
+
+    CircularBuffer();
+    CircularBuffer(const value_type &value);
+
+    CircularBuffer(const CircularBuffer<T, N, Storage> &other);
+    CircularBuffer(CircularBuffer<T, N, Storage> &&other);
+
+    CircularBuffer<T, N, Storage> &operator=(const CircularBuffer<T, N, Storage> &other);
+    CircularBuffer<T, N, Storage> &operator=(CircularBuffer<T, N, Storage> &&other);
+
+    ~CircularBuffer();
+
+    // begin() and end() are used to iterate over all elements regardless of the current position of
+    // the front of the buffer.  Useful for initialization and clean up, as otherwise only the front
+    // element is expected to be accessed.
+    iterator begin();
+    const_iterator begin() const;
+
+    iterator end();
+    const_iterator end() const;
+
+    size_type size() const;
+
+    reference front();
+    const_reference front() const;
+
+    void swap(CircularBuffer<T, N, Storage> &other);
+
+    // Move the front forward to the next index, looping back to the beginning if the end of the
+    // array is reached.
+    void next();
+
+  private:
+    Storage mData;
+    size_type mFrontIndex;
+};
+
+template <class T, size_t N, class Storage>
+CircularBuffer<T, N, Storage>::CircularBuffer() : mFrontIndex(0)
+{}
+
+template <class T, size_t N, class Storage>
+CircularBuffer<T, N, Storage>::CircularBuffer(const value_type &value) : CircularBuffer()
+{
+    std::fill(begin(), end(), value);
+}
+
+template <class T, size_t N, class Storage>
+CircularBuffer<T, N, Storage>::CircularBuffer(const CircularBuffer<T, N, Storage> &other)
+{
+    *this = other;
+}
+
+template <class T, size_t N, class Storage>
+CircularBuffer<T, N, Storage>::CircularBuffer(CircularBuffer<T, N, Storage> &&other)
+    : CircularBuffer()
+{
+    swap(other);
+}
+
+template <class T, size_t N, class Storage>
+CircularBuffer<T, N, Storage> &CircularBuffer<T, N, Storage>::operator=(
+    const CircularBuffer<T, N, Storage> &other)
+{
+    std::copy(other.begin(), other.end(), begin());
+    mFrontIndex = other.mFrontIndex;
+    return *this;
+}
+
+template <class T, size_t N, class Storage>
+CircularBuffer<T, N, Storage> &CircularBuffer<T, N, Storage>::operator=(
+    CircularBuffer<T, N, Storage> &&other)
+{
+    swap(other);
+    return *this;
+}
+
+template <class T, size_t N, class Storage>
+CircularBuffer<T, N, Storage>::~CircularBuffer() = default;
+
+template <class T, size_t N, class Storage>
+ANGLE_INLINE typename CircularBuffer<T, N, Storage>::iterator CircularBuffer<T, N, Storage>::begin()
+{
+    return mData.begin();
+}
+
+template <class T, size_t N, class Storage>
+ANGLE_INLINE typename CircularBuffer<T, N, Storage>::const_iterator
+CircularBuffer<T, N, Storage>::begin() const
+{
+    return mData.begin();
+}
+
+template <class T, size_t N, class Storage>
+ANGLE_INLINE typename CircularBuffer<T, N, Storage>::iterator CircularBuffer<T, N, Storage>::end()
+{
+    return mData.end();
+}
+
+template <class T, size_t N, class Storage>
+ANGLE_INLINE typename CircularBuffer<T, N, Storage>::const_iterator
+CircularBuffer<T, N, Storage>::end() const
+{
+    return mData.end();
+}
+
+template <class T, size_t N, class Storage>
+ANGLE_INLINE typename CircularBuffer<T, N, Storage>::size_type CircularBuffer<T, N, Storage>::size()
+    const
+{
+    return N;
+}
+
+template <class T, size_t N, class Storage>
+ANGLE_INLINE typename CircularBuffer<T, N, Storage>::reference
+CircularBuffer<T, N, Storage>::front()
+{
+    ASSERT(mFrontIndex < size());
+    return mData[mFrontIndex];
+}
+
+template <class T, size_t N, class Storage>
+ANGLE_INLINE typename CircularBuffer<T, N, Storage>::const_reference
+CircularBuffer<T, N, Storage>::front() const
+{
+    ASSERT(mFrontIndex < size());
+    return mData[mFrontIndex];
+}
+
+template <class T, size_t N, class Storage>
+void CircularBuffer<T, N, Storage>::swap(CircularBuffer<T, N, Storage> &other)
+{
+    std::swap(mData, other.mData);
+    std::swap(mFrontIndex, other.mFrontIndex);
+}
+
+template <class T, size_t N, class Storage>
+void CircularBuffer<T, N, Storage>::next()
+{
+    mFrontIndex = (mFrontIndex + 1) % size();
+}
+}  // namespace angle
+
+#endif  // COMMON_CIRCULARBUFFER_H_