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diff --git a/gfx/skia/skia/include/private/base/SkTLogic.h b/gfx/skia/skia/include/private/base/SkTLogic.h
new file mode 100644
index 0000000000..26f363c946
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+++ b/gfx/skia/skia/include/private/base/SkTLogic.h
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2013 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ *
+ * This header provides some std:: features early in the skstd namespace
+ * and several Skia-specific additions in the sknonstd namespace.
+ */
+
+#ifndef SkTLogic_DEFINED
+#define SkTLogic_DEFINED
+
+#include <iterator>
+#include <type_traits>
+#include "include/private/base/SkTo.h"
+
+// The sknonstd namespace contains things we would like to be proposed and feel std-ish.
+namespace sknonstd {
+
+// The name 'copy' here is fraught with peril. In this case it means 'append', not 'overwrite'.
+// Alternate proposed names are 'propagate', 'augment', or 'append' (and 'add', but already taken).
+// std::experimental::propagate_const already exists for other purposes in TSv2.
+// These also follow the <dest, source> pattern used by boost.
+template <typename D, typename S> struct copy_const {
+    using type = std::conditional_t<std::is_const<S>::value, std::add_const_t<D>, D>;
+};
+template <typename D, typename S> using copy_const_t = typename copy_const<D, S>::type;
+
+template <typename D, typename S> struct copy_volatile {
+    using type = std::conditional_t<std::is_volatile<S>::value, std::add_volatile_t<D>, D>;
+};
+template <typename D, typename S> using copy_volatile_t = typename copy_volatile<D, S>::type;
+
+template <typename D, typename S> struct copy_cv {
+    using type = copy_volatile_t<copy_const_t<D, S>, S>;
+};
+template <typename D, typename S> using copy_cv_t = typename copy_cv<D, S>::type;
+
+// The name 'same' here means 'overwrite'.
+// Alternate proposed names are 'replace', 'transfer', or 'qualify_from'.
+// same_xxx<D, S> can be written as copy_xxx<remove_xxx_t<D>, S>
+template <typename D, typename S> using same_const = copy_const<std::remove_const_t<D>, S>;
+template <typename D, typename S> using same_const_t = typename same_const<D, S>::type;
+template <typename D, typename S> using same_volatile =copy_volatile<std::remove_volatile_t<D>,S>;
+template <typename D, typename S> using same_volatile_t = typename same_volatile<D, S>::type;
+template <typename D, typename S> using same_cv = copy_cv<std::remove_cv_t<D>, S>;
+template <typename D, typename S> using same_cv_t = typename same_cv<D, S>::type;
+
+}  // namespace sknonstd
+
+template <typename Container>
+constexpr int SkCount(const Container& c) { return SkTo<int>(std::size(c)); }
+
+#endif