Revert "Import Chromium base/numerics to resolve integer overflow."

This reverts commit d9713f05fdcecab8428d39034c6b84cd0bbd2920.

This is breaking compile.

8 files changed, 0 insertions, 1195 deletions

diff --git a/third_party/logging.h b/third_party/logging.h
deleted file mode 100644
index 3629e84d4a..0000000000
--- a/third_party/logging.h
+++ /dev/null
@@ -1,18 +0,0 @@
-// Copyright (c) 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef BASE_LOGGING_H_
-#define BASE_LOGGING_H_
-
-#include <stdlib.h>
-
-#define CHECK(condition)                                                \
-  if (!(condition)) {                                                   \
-    abort();                                                            \
-    *(reinterpret_cast<volatile char*>(NULL) + 42) = 0x42;              \
-  }
-
-#define NOTREACHED() abort()
-
-#endif  // BASE_LOGGING_H_
diff --git a/third_party/macros.h b/third_party/macros.h
deleted file mode 100644
index 93c44857a9..0000000000
--- a/third_party/macros.h
+++ /dev/null
@@ -1,87 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// This file contains macros and macro-like constructs (e.g., templates) that
-// are commonly used throughout Chromium source. (It may also contain things
-// that are closely related to things that are commonly used that belong in this
-// file.)
-
-#ifndef BASE_MACROS_H_
-#define BASE_MACROS_H_
-
-// The COMPILE_ASSERT macro can be used to verify that a compile time
-// expression is true. For example, you could use it to verify the
-// size of a static array:
-//
-//   COMPILE_ASSERT(ARRAYSIZE_UNSAFE(content_type_names) == CONTENT_NUM_TYPES,
-//                  content_type_names_incorrect_size);
-//
-// or to make sure a struct is smaller than a certain size:
-//
-//   COMPILE_ASSERT(sizeof(foo) < 128, foo_too_large);
-//
-// The second argument to the macro is the name of the variable. If
-// the expression is false, most compilers will issue a warning/error
-// containing the name of the variable.
-
-#undef COMPILE_ASSERT
-
-#if __cplusplus >= 201103L
-
-// Under C++11, just use static_assert.
-#define COMPILE_ASSERT(expr, msg) static_assert(expr, #msg)
-
-#else
-
-template <bool>
-struct CompileAssert {
-};
-
-#define COMPILE_ASSERT(expr, msg) \
-  typedef CompileAssert<(bool(expr))> msg[bool(expr) ? 1 : -1] ALLOW_UNUSED
-
-// Implementation details of COMPILE_ASSERT:
-//
-// - COMPILE_ASSERT works by defining an array type that has -1
-//   elements (and thus is invalid) when the expression is false.
-//
-// - The simpler definition
-//
-//     #define COMPILE_ASSERT(expr, msg) typedef char msg[(expr) ? 1 : -1]
-//
-//   does not work, as gcc supports variable-length arrays whose sizes
-//   are determined at run-time (this is gcc's extension and not part
-//   of the C++ standard).  As a result, gcc fails to reject the
-//   following code with the simple definition:
-//
-//     int foo;
-//     COMPILE_ASSERT(foo, msg); // not supposed to compile as foo is
-//                               // not a compile-time constant.
-//
-// - By using the type CompileAssert<(bool(expr))>, we ensures that
-//   expr is a compile-time constant.  (Template arguments must be
-//   determined at compile-time.)
-//
-// - The outer parentheses in CompileAssert<(bool(expr))> are necessary
-//   to work around a bug in gcc 3.4.4 and 4.0.1.  If we had written
-//
-//     CompileAssert<bool(expr)>
-//
-//   instead, these compilers will refuse to compile
-//
-//     COMPILE_ASSERT(5 > 0, some_message);
-//
-//   (They seem to think the ">" in "5 > 0" marks the end of the
-//   template argument list.)
-//
-// - The array size is (bool(expr) ? 1 : -1), instead of simply
-//
-//     ((expr) ? 1 : -1).
-//
-//   This is to avoid running into a bug in MS VC 7.1, which
-//   causes ((0.0) ? 1 : -1) to incorrectly evaluate to 1.
-
-#endif
-
-#endif  // BASE_MACROS_H_
diff --git a/third_party/numerics/OWNERS b/third_party/numerics/OWNERS
deleted file mode 100644
index f7816afe81..0000000000
--- a/third_party/numerics/OWNERS
+++ /dev/null
@@ -1,3 +0,0 @@
-jschuh@chromium.org
-tsepez@chromium.org
-palmer@chromium.org
diff --git a/third_party/numerics/safe_conversions.h b/third_party/numerics/safe_conversions.h
deleted file mode 100644
index 681dc0a9cc..0000000000
--- a/third_party/numerics/safe_conversions.h
+++ /dev/null
@@ -1,64 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef BASE_SAFE_CONVERSIONS_H_
-#define BASE_SAFE_CONVERSIONS_H_
-
-#include <limits>
-
-#include "../logging.h"
-#include "safe_conversions_impl.h"
-
-namespace base {
-
-// Convenience function that returns true if the supplied value is in range
-// for the destination type.
-template <typename Dst, typename Src>
-inline bool IsValueInRangeForNumericType(Src value) {
-  return internal::DstRangeRelationToSrcRange<Dst>(value) ==
-         internal::RANGE_VALID;
-}
-
-// checked_cast<> is analogous to static_cast<> for numeric types,
-// except that it CHECKs that the specified numeric conversion will not
-// overflow or underflow. NaN source will always trigger a CHECK.
-template <typename Dst, typename Src>
-inline Dst checked_cast(Src value) {
-  CHECK(IsValueInRangeForNumericType<Dst>(value));
-  return static_cast<Dst>(value);
-}
-
-// saturated_cast<> is analogous to static_cast<> for numeric types, except
-// that the specified numeric conversion will saturate rather than overflow or
-// underflow. NaN assignment to an integral will trigger a CHECK condition.
-template <typename Dst, typename Src>
-inline Dst saturated_cast(Src value) {
-  // Optimization for floating point values, which already saturate.
-  if (std::numeric_limits<Dst>::is_iec559)
-    return static_cast<Dst>(value);
-
-  switch (internal::DstRangeRelationToSrcRange<Dst>(value)) {
-    case internal::RANGE_VALID:
-      return static_cast<Dst>(value);
-
-    case internal::RANGE_UNDERFLOW:
-      return std::numeric_limits<Dst>::min();
-
-    case internal::RANGE_OVERFLOW:
-      return std::numeric_limits<Dst>::max();
-
-    // Should fail only on attempting to assign NaN to a saturated integer.
-    case internal::RANGE_INVALID:
-      CHECK(false);
-      return std::numeric_limits<Dst>::max();
-  }
-
-  NOTREACHED();
-  return static_cast<Dst>(value);
-}
-
-}  // namespace base
-
-#endif  // BASE_SAFE_CONVERSIONS_H_
-
diff --git a/third_party/numerics/safe_conversions_impl.h b/third_party/numerics/safe_conversions_impl.h
deleted file mode 100644
index a357e518d1..0000000000
--- a/third_party/numerics/safe_conversions_impl.h
+++ /dev/null
@@ -1,217 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef BASE_SAFE_CONVERSIONS_IMPL_H_
-#define BASE_SAFE_CONVERSIONS_IMPL_H_
-
-#include <limits>
-
-#include "../macros.h"
-#include "../template_util.h"
-
-namespace base {
-namespace internal {
-
-// The std library doesn't provide a binary max_exponent for integers, however
-// we can compute one by adding one to the number of non-sign bits. This allows
-// for accurate range comparisons between floating point and integer types.
-template <typename NumericType>
-struct MaxExponent {
-  static const int value = std::numeric_limits<NumericType>::is_iec559
-                               ? std::numeric_limits<NumericType>::max_exponent
-                               : (sizeof(NumericType) * 8 + 1 -
-                                  std::numeric_limits<NumericType>::is_signed);
-};
-
-enum IntegerRepresentation {
-  INTEGER_REPRESENTATION_UNSIGNED,
-  INTEGER_REPRESENTATION_SIGNED
-};
-
-// A range for a given nunmeric Src type is contained for a given numeric Dst
-// type if both numeric_limits<Src>::max() <= numeric_limits<Dst>::max() and
-// numeric_limits<Src>::min() >= numeric_limits<Dst>::min() are true.
-// We implement this as template specializations rather than simple static
-// comparisons to ensure type correctness in our comparisons.
-enum NumericRangeRepresentation {
-  NUMERIC_RANGE_NOT_CONTAINED,
-  NUMERIC_RANGE_CONTAINED
-};
-
-// Helper templates to statically determine if our destination type can contain
-// maximum and minimum values represented by the source type.
-
-template <
-    typename Dst,
-    typename Src,
-    IntegerRepresentation DstSign = std::numeric_limits<Dst>::is_signed
-                                            ? INTEGER_REPRESENTATION_SIGNED
-                                            : INTEGER_REPRESENTATION_UNSIGNED,
-    IntegerRepresentation SrcSign =
-        std::numeric_limits<Src>::is_signed
-            ? INTEGER_REPRESENTATION_SIGNED
-            : INTEGER_REPRESENTATION_UNSIGNED >
-struct StaticDstRangeRelationToSrcRange;
-
-// Same sign: Dst is guaranteed to contain Src only if its range is equal or
-// larger.
-template <typename Dst, typename Src, IntegerRepresentation Sign>
-struct StaticDstRangeRelationToSrcRange<Dst, Src, Sign, Sign> {
-  static const NumericRangeRepresentation value =
-      MaxExponent<Dst>::value >= MaxExponent<Src>::value
-          ? NUMERIC_RANGE_CONTAINED
-          : NUMERIC_RANGE_NOT_CONTAINED;
-};
-
-// Unsigned to signed: Dst is guaranteed to contain source only if its range is
-// larger.
-template <typename Dst, typename Src>
-struct StaticDstRangeRelationToSrcRange<Dst,
-                                        Src,
-                                        INTEGER_REPRESENTATION_SIGNED,
-                                        INTEGER_REPRESENTATION_UNSIGNED> {
-  static const NumericRangeRepresentation value =
-      MaxExponent<Dst>::value > MaxExponent<Src>::value
-          ? NUMERIC_RANGE_CONTAINED
-          : NUMERIC_RANGE_NOT_CONTAINED;
-};
-
-// Signed to unsigned: Dst cannot be statically determined to contain Src.
-template <typename Dst, typename Src>
-struct StaticDstRangeRelationToSrcRange<Dst,
-                                        Src,
-                                        INTEGER_REPRESENTATION_UNSIGNED,
-                                        INTEGER_REPRESENTATION_SIGNED> {
-  static const NumericRangeRepresentation value = NUMERIC_RANGE_NOT_CONTAINED;
-};
-
-enum RangeConstraint {
-  RANGE_VALID = 0x0,  // Value can be represented by the destination type.
-  RANGE_UNDERFLOW = 0x1,  // Value would overflow.
-  RANGE_OVERFLOW = 0x2,  // Value would underflow.
-  RANGE_INVALID = RANGE_UNDERFLOW | RANGE_OVERFLOW  // Invalid (i.e. NaN).
-};
-
-// Helper function for coercing an int back to a RangeContraint.
-inline RangeConstraint GetRangeConstraint(int integer_range_constraint) {
-  assert(integer_range_constraint >= RANGE_VALID &&
-         integer_range_constraint <= RANGE_INVALID);
-  return static_cast<RangeConstraint>(integer_range_constraint);
-}
-
-// This function creates a RangeConstraint from an upper and lower bound
-// check by taking advantage of the fact that only NaN can be out of range in
-// both directions at once.
-inline RangeConstraint GetRangeConstraint(bool is_in_upper_bound,
-                                   bool is_in_lower_bound) {
-  return GetRangeConstraint((is_in_upper_bound ? 0 : RANGE_OVERFLOW) |
-                            (is_in_lower_bound ? 0 : RANGE_UNDERFLOW));
-}
-
-template <
-    typename Dst,
-    typename Src,
-    IntegerRepresentation DstSign = std::numeric_limits<Dst>::is_signed
-                                            ? INTEGER_REPRESENTATION_SIGNED
-                                            : INTEGER_REPRESENTATION_UNSIGNED,
-    IntegerRepresentation SrcSign = std::numeric_limits<Src>::is_signed
-                                            ? INTEGER_REPRESENTATION_SIGNED
-                                            : INTEGER_REPRESENTATION_UNSIGNED,
-    NumericRangeRepresentation DstRange =
-        StaticDstRangeRelationToSrcRange<Dst, Src>::value >
-struct DstRangeRelationToSrcRangeImpl;
-
-// The following templates are for ranges that must be verified at runtime. We
-// split it into checks based on signedness to avoid confusing casts and
-// compiler warnings on signed an unsigned comparisons.
-
-// Dst range is statically determined to contain Src: Nothing to check.
-template <typename Dst,
-          typename Src,
-          IntegerRepresentation DstSign,
-          IntegerRepresentation SrcSign>
-struct DstRangeRelationToSrcRangeImpl<Dst,
-                                      Src,
-                                      DstSign,
-                                      SrcSign,
-                                      NUMERIC_RANGE_CONTAINED> {
-  static RangeConstraint Check(Src value) { return RANGE_VALID; }
-};
-
-// Signed to signed narrowing: Both the upper and lower boundaries may be
-// exceeded.
-template <typename Dst, typename Src>
-struct DstRangeRelationToSrcRangeImpl<Dst,
-                                      Src,
-                                      INTEGER_REPRESENTATION_SIGNED,
-                                      INTEGER_REPRESENTATION_SIGNED,
-                                      NUMERIC_RANGE_NOT_CONTAINED> {
-  static RangeConstraint Check(Src value) {
-    return std::numeric_limits<Dst>::is_iec559
-               ? GetRangeConstraint(value <= std::numeric_limits<Dst>::max(),
-                                    value >= -std::numeric_limits<Dst>::max())
-               : GetRangeConstraint(value <= std::numeric_limits<Dst>::max(),
-                                    value >= std::numeric_limits<Dst>::min());
-  }
-};
-
-// Unsigned to unsigned narrowing: Only the upper boundary can be exceeded.
-template <typename Dst, typename Src>
-struct DstRangeRelationToSrcRangeImpl<Dst,
-                                      Src,
-                                      INTEGER_REPRESENTATION_UNSIGNED,
-                                      INTEGER_REPRESENTATION_UNSIGNED,
-                                      NUMERIC_RANGE_NOT_CONTAINED> {
-  static RangeConstraint Check(Src value) {
-    return GetRangeConstraint(value <= std::numeric_limits<Dst>::max(), true);
-  }
-};
-
-// Unsigned to signed: The upper boundary may be exceeded.
-template <typename Dst, typename Src>
-struct DstRangeRelationToSrcRangeImpl<Dst,
-                                      Src,
-                                      INTEGER_REPRESENTATION_SIGNED,
-                                      INTEGER_REPRESENTATION_UNSIGNED,
-                                      NUMERIC_RANGE_NOT_CONTAINED> {
-  static RangeConstraint Check(Src value) {
-    return sizeof(Dst) > sizeof(Src)
-               ? RANGE_VALID
-               : GetRangeConstraint(
-                     value <= static_cast<Src>(std::numeric_limits<Dst>::max()),
-                     true);
-  }
-};
-
-// Signed to unsigned: The upper boundary may be exceeded for a narrower Dst,
-// and any negative value exceeds the lower boundary.
-template <typename Dst, typename Src>
-struct DstRangeRelationToSrcRangeImpl<Dst,
-                                      Src,
-                                      INTEGER_REPRESENTATION_UNSIGNED,
-                                      INTEGER_REPRESENTATION_SIGNED,
-                                      NUMERIC_RANGE_NOT_CONTAINED> {
-  static RangeConstraint Check(Src value) {
-    return (MaxExponent<Dst>::value >= MaxExponent<Src>::value)
-               ? GetRangeConstraint(true, value >= static_cast<Src>(0))
-               : GetRangeConstraint(
-                     value <= static_cast<Src>(std::numeric_limits<Dst>::max()),
-                     value >= static_cast<Src>(0));
-  }
-};
-
-template <typename Dst, typename Src>
-inline RangeConstraint DstRangeRelationToSrcRange(Src value) {
-  COMPILE_ASSERT(std::numeric_limits<Src>::is_specialized,
-                 argument_must_be_numeric);
-  COMPILE_ASSERT(std::numeric_limits<Dst>::is_specialized,
-                 result_must_be_numeric);
-  return DstRangeRelationToSrcRangeImpl<Dst, Src>::Check(value);
-}
-
-}  // namespace internal
-}  // namespace base
-
-#endif  // BASE_SAFE_CONVERSIONS_IMPL_H_
-
diff --git a/third_party/numerics/safe_math.h b/third_party/numerics/safe_math.h
deleted file mode 100644
index 4b38ff2b1f..0000000000
--- a/third_party/numerics/safe_math.h
+++ /dev/null
@@ -1,271 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef BASE_SAFE_MATH_H_
-#define BASE_SAFE_MATH_H_
-
-#include "safe_math_impl.h"
-
-namespace base {
-
-namespace internal {
-
-// CheckedNumeric implements all the logic and operators for detecting integer
-// boundary conditions such as overflow, underflow, and invalid conversions.
-// The CheckedNumeric type implicitly converts from floating point and integer
-// data types, and contains overloads for basic arithmetic operations (i.e.: +,
-// -, *, /, %).
-//
-// The following methods convert from CheckedNumeric to standard numeric values:
-// IsValid() - Returns true if the underlying numeric value is valid (i.e. has
-//             has not wrapped and is not the result of an invalid conversion).
-// ValueOrDie() - Returns the underlying value. If the state is not valid this
-//                call will crash on a CHECK.
-// ValueOrDefault() - Returns the current value, or the supplied default if the
-//                    state is not valid.
-// ValueFloating() - Returns the underlying floating point value (valid only
-//                   only for floating point CheckedNumeric types).
-//
-// Bitwise operations are explicitly not supported, because correct
-// handling of some cases (e.g. sign manipulation) is ambiguous. Comparison
-// operations are explicitly not supported because they could result in a crash
-// on a CHECK condition. You should use patterns like the following for these
-// operations:
-// Bitwise operation:
-//     CheckedNumeric<int> checked_int = untrusted_input_value;
-//     int x = checked_int.ValueOrDefault(0) | kFlagValues;
-// Comparison:
-//   CheckedNumeric<size_t> checked_size;
-//   CheckedNumeric<int> checked_size = untrusted_input_value;
-//   checked_size = checked_size + HEADER LENGTH;
-//   if (checked_size.IsValid() && checked_size.ValueOrDie() < buffer_size)
-//     Do stuff...
-template <typename T>
-class CheckedNumeric {
- public:
-  typedef T type;
-
-  CheckedNumeric() {}
-
-  // Copy constructor.
-  template <typename Src>
-  CheckedNumeric(const CheckedNumeric<Src>& rhs)
-      : state_(rhs.ValueUnsafe(), rhs.validity()) {}
-
-  template <typename Src>
-  CheckedNumeric(Src value, RangeConstraint validity)
-      : state_(value, validity) {}
-
-  // This is not an explicit constructor because we implicitly upgrade regular
-  // numerics to CheckedNumerics to make them easier to use.
-  template <typename Src>
-  CheckedNumeric(Src value)
-      : state_(value) {
-    COMPILE_ASSERT(std::numeric_limits<Src>::is_specialized,
-                   argument_must_be_numeric);
-  }
-
-  // IsValid() is the public API to test if a CheckedNumeric is currently valid.
-  bool IsValid() const { return validity() == RANGE_VALID; }
-
-  // ValueOrDie() The primary accessor for the underlying value. If the current
-  // state is not valid it will CHECK and crash.
-  T ValueOrDie() const {
-    CHECK(IsValid());
-    return state_.value();
-  }
-
-  // ValueOrDefault(T default_value) A convenience method that returns the
-  // current value if the state is valid, and the supplied default_value for
-  // any other state.
-  T ValueOrDefault(T default_value) const {
-    return IsValid() ? state_.value() : default_value;
-  }
-
-  // ValueFloating() - Since floating point values include their validity state,
-  // we provide an easy method for extracting them directly, without a risk of
-  // crashing on a CHECK.
-  T ValueFloating() const {
-    COMPILE_ASSERT(std::numeric_limits<T>::is_iec559, argument_must_be_float);
-    return CheckedNumeric<T>::cast(*this).ValueUnsafe();
-  }
-
-  // validity() - DO NOT USE THIS IN EXTERNAL CODE - It is public right now for
-  // tests and to avoid a big matrix of friend operator overloads. But the
-  // values it returns are likely to change in the future.
-  // Returns: current validity state (i.e. valid, overflow, underflow, nan).
-  // TODO(jschuh): crbug.com/332611 Figure out and implement semantics for
-  // saturation/wrapping so we can expose this state consistently and implement
-  // saturated arithmetic.
-  RangeConstraint validity() const { return state_.validity(); }
-
-  // ValueUnsafe() - DO NOT USE THIS IN EXTERNAL CODE - It is public right now
-  // for tests and to avoid a big matrix of friend operator overloads. But the
-  // values it returns are likely to change in the future.
-  // Returns: the raw numeric value, regardless of the current state.
-  // TODO(jschuh): crbug.com/332611 Figure out and implement semantics for
-  // saturation/wrapping so we can expose this state consistently and implement
-  // saturated arithmetic.
-  T ValueUnsafe() const { return state_.value(); }
-
-  // Prototypes for the supported arithmetic operator overloads.
-  template <typename Src> CheckedNumeric& operator+=(Src rhs);
-  template <typename Src> CheckedNumeric& operator-=(Src rhs);
-  template <typename Src> CheckedNumeric& operator*=(Src rhs);
-  template <typename Src> CheckedNumeric& operator/=(Src rhs);
-  template <typename Src> CheckedNumeric& operator%=(Src rhs);
-
-  CheckedNumeric operator-() const {
-    RangeConstraint validity;
-    T value = CheckedNeg(state_.value(), &validity);
-    // Negation is always valid for floating point.
-    if (std::numeric_limits<T>::is_iec559)
-      return CheckedNumeric<T>(value);
-
-    validity = GetRangeConstraint(state_.validity() | validity);
-    return CheckedNumeric<T>(value, validity);
-  }
-
-  CheckedNumeric Abs() const {
-    RangeConstraint validity;
-    T value = CheckedAbs(state_.value(), &validity);
-    // Absolute value is always valid for floating point.
-    if (std::numeric_limits<T>::is_iec559)
-      return CheckedNumeric<T>(value);
-
-    validity = GetRangeConstraint(state_.validity() | validity);
-    return CheckedNumeric<T>(value, validity);
-  }
-
-  CheckedNumeric& operator++() {
-    *this += 1;
-    return *this;
-  }
-
-  CheckedNumeric operator++(int) {
-    CheckedNumeric value = *this;
-    *this += 1;
-    return value;
-  }
-
-  CheckedNumeric& operator--() {
-    *this -= 1;
-    return *this;
-  }
-
-  CheckedNumeric operator--(int) {
-    CheckedNumeric value = *this;
-    *this -= 1;
-    return value;
-  }
-
-  // These static methods behave like a convenience cast operator targeting
-  // the desired CheckedNumeric type. As an optimization, a reference is
-  // returned when Src is the same type as T.
-  template <typename Src>
-  static CheckedNumeric<T> cast(
-      Src u,
-      typename enable_if<std::numeric_limits<Src>::is_specialized, int>::type =
-          0) {
-    return u;
-  }
-
-  template <typename Src>
-  static CheckedNumeric<T> cast(
-      const CheckedNumeric<Src>& u,
-      typename enable_if<!is_same<Src, T>::value, int>::type = 0) {
-    return u;
-  }
-
-  static const CheckedNumeric<T>& cast(const CheckedNumeric<T>& u) { return u; }
-
- private:
-  CheckedNumericState<T> state_;
-};
-
-// This is the boilerplate for the standard arithmetic operator overloads. A
-// macro isn't the prettiest solution, but it beats rewriting these five times.
-// Some details worth noting are:
-//  * We apply the standard arithmetic promotions.
-//  * We skip range checks for floating points.
-//  * We skip range checks for destination integers with sufficient range.
-// TODO(jschuh): extract these out into templates.
-#define BASE_NUMERIC_ARITHMETIC_OPERATORS(NAME, OP, COMPOUND_OP)              \
-  /* Binary arithmetic operator for CheckedNumerics of the same type. */      \
-  template <typename T>                                                       \
-  CheckedNumeric<typename ArithmeticPromotion<T>::type> operator OP(          \
-      const CheckedNumeric<T>& lhs, const CheckedNumeric<T>& rhs) {           \
-    typedef typename ArithmeticPromotion<T>::type Promotion;                  \
-    /* Floating point always takes the fast path */                           \
-    if (std::numeric_limits<T>::is_iec559)                                    \
-      return CheckedNumeric<T>(lhs.ValueUnsafe() OP rhs.ValueUnsafe());       \
-    if (IsIntegerArithmeticSafe<Promotion, T, T>::value)                      \
-      return CheckedNumeric<Promotion>(                                       \
-          lhs.ValueUnsafe() OP rhs.ValueUnsafe(),                             \
-          GetRangeConstraint(rhs.validity() | lhs.validity()));               \
-    RangeConstraint validity = RANGE_VALID;                                   \
-    T result = Checked##NAME(static_cast<Promotion>(lhs.ValueUnsafe()),       \
-                             static_cast<Promotion>(rhs.ValueUnsafe()),       \
-                             &validity);                                      \
-    return CheckedNumeric<Promotion>(                                         \
-        result,                                                               \
-        GetRangeConstraint(validity | lhs.validity() | rhs.validity()));      \
-  }                                                                           \
-  /* Assignment arithmetic operator implementation from CheckedNumeric. */    \
-  template <typename T>                                                       \
-  template <typename Src>                                                     \
-  CheckedNumeric<T>& CheckedNumeric<T>::operator COMPOUND_OP(Src rhs) {       \
-    *this = CheckedNumeric<T>::cast(*this) OP CheckedNumeric<Src>::cast(rhs); \
-    return *this;                                                             \
-  }                                                                           \
-  /* Binary arithmetic operator for CheckedNumeric of different type. */      \
-  template <typename T, typename Src>                                         \
-  CheckedNumeric<typename ArithmeticPromotion<T, Src>::type> operator OP(     \
-      const CheckedNumeric<Src>& lhs, const CheckedNumeric<T>& rhs) {         \
-    typedef typename ArithmeticPromotion<T, Src>::type Promotion;             \
-    if (IsIntegerArithmeticSafe<Promotion, T, Src>::value)                    \
-      return CheckedNumeric<Promotion>(                                       \
-          lhs.ValueUnsafe() OP rhs.ValueUnsafe(),                             \
-          GetRangeConstraint(rhs.validity() | lhs.validity()));               \
-    return CheckedNumeric<Promotion>::cast(lhs)                               \
-        OP CheckedNumeric<Promotion>::cast(rhs);                              \
-  }                                                                           \
-  /* Binary arithmetic operator for left CheckedNumeric and right numeric. */ \
-  template <typename T, typename Src>                                         \
-  CheckedNumeric<typename ArithmeticPromotion<T, Src>::type> operator OP(     \
-      const CheckedNumeric<T>& lhs, Src rhs) {                                \
-    typedef typename ArithmeticPromotion<T, Src>::type Promotion;             \
-    if (IsIntegerArithmeticSafe<Promotion, T, Src>::value)                    \
-      return CheckedNumeric<Promotion>(lhs.ValueUnsafe() OP rhs,              \
-                                       lhs.validity());                       \
-    return CheckedNumeric<Promotion>::cast(lhs)                               \
-        OP CheckedNumeric<Promotion>::cast(rhs);                              \
-  }                                                                           \
-  /* Binary arithmetic operator for right numeric and left CheckedNumeric. */ \
-  template <typename T, typename Src>                                         \
-  CheckedNumeric<typename ArithmeticPromotion<T, Src>::type> operator OP(     \
-      Src lhs, const CheckedNumeric<T>& rhs) {                                \
-    typedef typename ArithmeticPromotion<T, Src>::type Promotion;             \
-    if (IsIntegerArithmeticSafe<Promotion, T, Src>::value)                    \
-      return CheckedNumeric<Promotion>(lhs OP rhs.ValueUnsafe(),              \
-                                       rhs.validity());                       \
-    return CheckedNumeric<Promotion>::cast(lhs)                               \
-        OP CheckedNumeric<Promotion>::cast(rhs);                              \
-  }
-
-BASE_NUMERIC_ARITHMETIC_OPERATORS(Add, +, += )
-BASE_NUMERIC_ARITHMETIC_OPERATORS(Sub, -, -= )
-BASE_NUMERIC_ARITHMETIC_OPERATORS(Mul, *, *= )
-BASE_NUMERIC_ARITHMETIC_OPERATORS(Div, /, /= )
-BASE_NUMERIC_ARITHMETIC_OPERATORS(Mod, %, %= )
-
-#undef BASE_NUMERIC_ARITHMETIC_OPERATORS
-
-}  // namespace internal
-
-using internal::CheckedNumeric;
-
-}  // namespace base
-
-#endif  // BASE_SAFE_MATH_H_
diff --git a/third_party/numerics/safe_math_impl.h b/third_party/numerics/safe_math_impl.h
deleted file mode 100644
index 4bf59e64e0..0000000000
--- a/third_party/numerics/safe_math_impl.h
+++ /dev/null
@@ -1,502 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef SAFE_MATH_IMPL_H_
-#define SAFE_MATH_IMPL_H_
-
-#include <stdint.h>
-
-#include <cmath>
-#include <cstdlib>
-#include <limits>
-
-#include "../macros.h"
-#include "../template_util.h"
-#include "safe_conversions.h"
-
-namespace base {
-namespace internal {
-
-// Everything from here up to the floating point operations is portable C++,
-// but it may not be fast. This code could be split based on
-// platform/architecture and replaced with potentially faster implementations.
-
-// Integer promotion templates used by the portable checked integer arithmetic.
-template <size_t Size, bool IsSigned>
-struct IntegerForSizeAndSign;
-template <>
-struct IntegerForSizeAndSign<1, true> {
-  typedef int8_t type;
-};
-template <>
-struct IntegerForSizeAndSign<1, false> {
-  typedef uint8_t type;
-};
-template <>
-struct IntegerForSizeAndSign<2, true> {
-  typedef int16_t type;
-};
-template <>
-struct IntegerForSizeAndSign<2, false> {
-  typedef uint16_t type;
-};
-template <>
-struct IntegerForSizeAndSign<4, true> {
-  typedef int32_t type;
-};
-template <>
-struct IntegerForSizeAndSign<4, false> {
-  typedef uint32_t type;
-};
-template <>
-struct IntegerForSizeAndSign<8, true> {
-  typedef int64_t type;
-};
-template <>
-struct IntegerForSizeAndSign<8, false> {
-  typedef uint64_t type;
-};
-
-// WARNING: We have no IntegerForSizeAndSign<16, *>. If we ever add one to
-// support 128-bit math, then the ArithmeticPromotion template below will need
-// to be updated (or more likely replaced with a decltype expression).
-
-template <typename Integer>
-struct UnsignedIntegerForSize {
-  typedef typename enable_if<
-      std::numeric_limits<Integer>::is_integer,
-      typename IntegerForSizeAndSign<sizeof(Integer), false>::type>::type type;
-};
-
-template <typename Integer>
-struct SignedIntegerForSize {
-  typedef typename enable_if<
-      std::numeric_limits<Integer>::is_integer,
-      typename IntegerForSizeAndSign<sizeof(Integer), true>::type>::type type;
-};
-
-template <typename Integer>
-struct TwiceWiderInteger {
-  typedef typename enable_if<
-      std::numeric_limits<Integer>::is_integer,
-      typename IntegerForSizeAndSign<
-          sizeof(Integer) * 2,
-          std::numeric_limits<Integer>::is_signed>::type>::type type;
-};
-
-template <typename Integer>
-struct PositionOfSignBit {
-  static const typename enable_if<std::numeric_limits<Integer>::is_integer,
-                                  size_t>::type value = 8 * sizeof(Integer) - 1;
-};
-
-// Helper templates for integer manipulations.
-
-template <typename T>
-bool HasSignBit(T x) {
-  // Cast to unsigned since right shift on signed is undefined.
-  return !!(static_cast<typename UnsignedIntegerForSize<T>::type>(x) >>
-            PositionOfSignBit<T>::value);
-}
-
-// This wrapper undoes the standard integer promotions.
-template <typename T>
-T BinaryComplement(T x) {
-  return ~x;
-}
-
-// Here are the actual portable checked integer math implementations.
-// TODO(jschuh): Break this code out from the enable_if pattern and find a clean
-// way to coalesce things into the CheckedNumericState specializations below.
-
-template <typename T>
-typename enable_if<std::numeric_limits<T>::is_integer, T>::type
-CheckedAdd(T x, T y, RangeConstraint* validity) {
-  // Since the value of x+y is undefined if we have a signed type, we compute
-  // it using the unsigned type of the same size.
-  typedef typename UnsignedIntegerForSize<T>::type UnsignedDst;
-  UnsignedDst ux = static_cast<UnsignedDst>(x);
-  UnsignedDst uy = static_cast<UnsignedDst>(y);
-  UnsignedDst uresult = ux + uy;
-  // Addition is valid if the sign of (x + y) is equal to either that of x or
-  // that of y.
-  if (std::numeric_limits<T>::is_signed) {
-    if (HasSignBit(BinaryComplement((uresult ^ ux) & (uresult ^ uy))))
-      *validity = RANGE_VALID;
-    else  // Direction of wrap is inverse of result sign.
-      *validity = HasSignBit(uresult) ? RANGE_OVERFLOW : RANGE_UNDERFLOW;
-
-  } else {  // Unsigned is either valid or overflow.
-    *validity = BinaryComplement(x) >= y ? RANGE_VALID : RANGE_OVERFLOW;
-  }
-  return static_cast<T>(uresult);
-}
-
-template <typename T>
-typename enable_if<std::numeric_limits<T>::is_integer, T>::type
-CheckedSub(T x, T y, RangeConstraint* validity) {
-  // Since the value of x+y is undefined if we have a signed type, we compute
-  // it using the unsigned type of the same size.
-  typedef typename UnsignedIntegerForSize<T>::type UnsignedDst;
-  UnsignedDst ux = static_cast<UnsignedDst>(x);
-  UnsignedDst uy = static_cast<UnsignedDst>(y);
-  UnsignedDst uresult = ux - uy;
-  // Subtraction is valid if either x and y have same sign, or (x-y) and x have
-  // the same sign.
-  if (std::numeric_limits<T>::is_signed) {
-    if (HasSignBit(BinaryComplement((uresult ^ ux) & (ux ^ uy))))
-      *validity = RANGE_VALID;
-    else  // Direction of wrap is inverse of result sign.
-      *validity = HasSignBit(uresult) ? RANGE_OVERFLOW : RANGE_UNDERFLOW;
-
-  } else {  // Unsigned is either valid or underflow.
-    *validity = x >= y ? RANGE_VALID : RANGE_UNDERFLOW;
-  }
-  return static_cast<T>(uresult);
-}
-
-// Integer multiplication is a bit complicated. In the fast case we just
-// we just promote to a twice wider type, and range check the result. In the
-// slow case we need to manually check that the result won't be truncated by
-// checking with division against the appropriate bound.
-template <typename T>
-typename enable_if<
-    std::numeric_limits<T>::is_integer && sizeof(T) * 2 <= sizeof(uintmax_t),
-    T>::type
-CheckedMul(T x, T y, RangeConstraint* validity) {
-  typedef typename TwiceWiderInteger<T>::type IntermediateType;
-  IntermediateType tmp =
-      static_cast<IntermediateType>(x) * static_cast<IntermediateType>(y);
-  *validity = DstRangeRelationToSrcRange<T>(tmp);
-  return static_cast<T>(tmp);
-}
-
-template <typename T>
-typename enable_if<std::numeric_limits<T>::is_integer&& std::numeric_limits<
-                       T>::is_signed&&(sizeof(T) * 2 > sizeof(uintmax_t)),
-                   T>::type
-CheckedMul(T x, T y, RangeConstraint* validity) {
-  // if either side is zero then the result will be zero.
-  if (!(x || y)) {
-    return RANGE_VALID;
-
-  } else if (x > 0) {
-    if (y > 0)
-      *validity =
-          x <= std::numeric_limits<T>::max() / y ? RANGE_VALID : RANGE_OVERFLOW;
-    else
-      *validity = y >= std::numeric_limits<T>::min() / x ? RANGE_VALID
-                                                         : RANGE_UNDERFLOW;
-
-  } else {
-    if (y > 0)
-      *validity = x >= std::numeric_limits<T>::min() / y ? RANGE_VALID
-                                                         : RANGE_UNDERFLOW;
-    else
-      *validity =
-          y >= std::numeric_limits<T>::max() / x ? RANGE_VALID : RANGE_OVERFLOW;
-  }
-
-  return x * y;
-}
-
-template <typename T>
-typename enable_if<std::numeric_limits<T>::is_integer &&
-                       !std::numeric_limits<T>::is_signed &&
-                       (sizeof(T) * 2 > sizeof(uintmax_t)),
-                   T>::type
-CheckedMul(T x, T y, RangeConstraint* validity) {
-  *validity = (y == 0 || x <= std::numeric_limits<T>::max() / y)
-                  ? RANGE_VALID
-                  : RANGE_OVERFLOW;
-  return x * y;
-}
-
-// Division just requires a check for an invalid negation on signed min/-1.
-template <typename T>
-T CheckedDiv(
-    T x,
-    T y,
-    RangeConstraint* validity,
-    typename enable_if<std::numeric_limits<T>::is_integer, int>::type = 0) {
-  if (std::numeric_limits<T>::is_signed && x == std::numeric_limits<T>::min() &&
-      y == static_cast<T>(-1)) {
-    *validity = RANGE_OVERFLOW;
-    return std::numeric_limits<T>::min();
-  }
-
-  *validity = RANGE_VALID;
-  return x / y;
-}
-
-template <typename T>
-typename enable_if<
-    std::numeric_limits<T>::is_integer&& std::numeric_limits<T>::is_signed,
-    T>::type
-CheckedMod(T x, T y, RangeConstraint* validity) {
-  *validity = y > 0 ? RANGE_VALID : RANGE_INVALID;
-  return x % y;
-}
-
-template <typename T>
-typename enable_if<
-    std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed,
-    T>::type
-CheckedMod(T x, T y, RangeConstraint* validity) {
-  *validity = RANGE_VALID;
-  return x % y;
-}
-
-template <typename T>
-typename enable_if<
-    std::numeric_limits<T>::is_integer&& std::numeric_limits<T>::is_signed,
-    T>::type
-CheckedNeg(T value, RangeConstraint* validity) {
-  *validity =
-      value != std::numeric_limits<T>::min() ? RANGE_VALID : RANGE_OVERFLOW;
-  // The negation of signed min is min, so catch that one.
-  return -value;
-}
-
-template <typename T>
-typename enable_if<
-    std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed,
-    T>::type
-CheckedNeg(T value, RangeConstraint* validity) {
-  // The only legal unsigned negation is zero.
-  *validity = value ? RANGE_UNDERFLOW : RANGE_VALID;
-  return static_cast<T>(
-      -static_cast<typename SignedIntegerForSize<T>::type>(value));
-}
-
-template <typename T>
-typename enable_if<
-    std::numeric_limits<T>::is_integer&& std::numeric_limits<T>::is_signed,
-    T>::type
-CheckedAbs(T value, RangeConstraint* validity) {
-  *validity =
-      value != std::numeric_limits<T>::min() ? RANGE_VALID : RANGE_OVERFLOW;
-  return std::abs(value);
-}
-
-template <typename T>
-typename enable_if<
-    std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed,
-    T>::type
-CheckedAbs(T value, RangeConstraint* validity) {
-  // Absolute value of a positive is just its identiy.
-  *validity = RANGE_VALID;
-  return value;
-}
-
-// These are the floating point stubs that the compiler needs to see. Only the
-// negation operation is ever called.
-#define BASE_FLOAT_ARITHMETIC_STUBS(NAME)                        \
-  template <typename T>                                          \
-  typename enable_if<std::numeric_limits<T>::is_iec559, T>::type \
-  Checked##NAME(T, T, RangeConstraint*) {                        \
-    NOTREACHED();                                                \
-    return 0;                                                    \
-  }
-
-BASE_FLOAT_ARITHMETIC_STUBS(Add)
-BASE_FLOAT_ARITHMETIC_STUBS(Sub)
-BASE_FLOAT_ARITHMETIC_STUBS(Mul)
-BASE_FLOAT_ARITHMETIC_STUBS(Div)
-BASE_FLOAT_ARITHMETIC_STUBS(Mod)
-
-#undef BASE_FLOAT_ARITHMETIC_STUBS
-
-template <typename T>
-typename enable_if<std::numeric_limits<T>::is_iec559, T>::type CheckedNeg(
-    T value,
-    RangeConstraint*) {
-  return -value;
-}
-
-template <typename T>
-typename enable_if<std::numeric_limits<T>::is_iec559, T>::type CheckedAbs(
-    T value,
-    RangeConstraint*) {
-  return std::abs(value);
-}
-
-// Floats carry around their validity state with them, but integers do not. So,
-// we wrap the underlying value in a specialization in order to hide that detail
-// and expose an interface via accessors.
-enum NumericRepresentation {
-  NUMERIC_INTEGER,
-  NUMERIC_FLOATING,
-  NUMERIC_UNKNOWN
-};
-
-template <typename NumericType>
-struct GetNumericRepresentation {
-  static const NumericRepresentation value =
-      std::numeric_limits<NumericType>::is_integer
-          ? NUMERIC_INTEGER
-          : (std::numeric_limits<NumericType>::is_iec559 ? NUMERIC_FLOATING
-                                                         : NUMERIC_UNKNOWN);
-};
-
-template <typename T, NumericRepresentation type =
-                          GetNumericRepresentation<T>::value>
-class CheckedNumericState {};
-
-// Integrals require quite a bit of additional housekeeping to manage state.
-template <typename T>
-class CheckedNumericState<T, NUMERIC_INTEGER> {
- private:
-  T value_;
-  RangeConstraint validity_;
-
- public:
-  template <typename Src, NumericRepresentation type>
-  friend class CheckedNumericState;
-
-  CheckedNumericState() : value_(0), validity_(RANGE_VALID) {}
-
-  template <typename Src>
-  CheckedNumericState(Src value, RangeConstraint validity)
-      : value_(value),
-        validity_(GetRangeConstraint(validity |
-                                     DstRangeRelationToSrcRange<T>(value))) {
-    COMPILE_ASSERT(std::numeric_limits<Src>::is_specialized,
-                   argument_must_be_numeric);
-  }
-
-  // Copy constructor.
-  template <typename Src>
-  CheckedNumericState(const CheckedNumericState<Src>& rhs)
-      : value_(static_cast<T>(rhs.value())),
-        validity_(GetRangeConstraint(
-            rhs.validity() | DstRangeRelationToSrcRange<T>(rhs.value()))) {}
-
-  template <typename Src>
-  explicit CheckedNumericState(
-      Src value,
-      typename enable_if<std::numeric_limits<Src>::is_specialized, int>::type =
-          0)
-      : value_(static_cast<T>(value)),
-        validity_(DstRangeRelationToSrcRange<T>(value)) {}
-
-  RangeConstraint validity() const { return validity_; }
-  T value() const { return value_; }
-};
-
-// Floating points maintain their own validity, but need translation wrappers.
-template <typename T>
-class CheckedNumericState<T, NUMERIC_FLOATING> {
- private:
-  T value_;
-
- public:
-  template <typename Src, NumericRepresentation type>
-  friend class CheckedNumericState;
-
-  CheckedNumericState() : value_(0.0) {}
-
-  template <typename Src>
-  CheckedNumericState(
-      Src value,
-      RangeConstraint validity,
-      typename enable_if<std::numeric_limits<Src>::is_integer, int>::type = 0) {
-    switch (DstRangeRelationToSrcRange<T>(value)) {
-      case RANGE_VALID:
-        value_ = static_cast<T>(value);
-        break;
-
-      case RANGE_UNDERFLOW:
-        value_ = -std::numeric_limits<T>::infinity();
-        break;
-
-      case RANGE_OVERFLOW:
-        value_ = std::numeric_limits<T>::infinity();
-        break;
-
-      case RANGE_INVALID:
-        value_ = std::numeric_limits<T>::quiet_NaN();
-        break;
-
-      default:
-        NOTREACHED();
-    }
-  }
-
-  template <typename Src>
-  explicit CheckedNumericState(
-      Src value,
-      typename enable_if<std::numeric_limits<Src>::is_specialized, int>::type =
-          0)
-      : value_(static_cast<T>(value)) {}
-
-  // Copy constructor.
-  template <typename Src>
-  CheckedNumericState(const CheckedNumericState<Src>& rhs)
-      : value_(static_cast<T>(rhs.value())) {}
-
-  RangeConstraint validity() const {
-    return GetRangeConstraint(value_ <= std::numeric_limits<T>::max(),
-                              value_ >= -std::numeric_limits<T>::max());
-  }
-  T value() const { return value_; }
-};
-
-// For integers less than 128-bit and floats 32-bit or larger, we can distil
-// C/C++ arithmetic promotions down to two simple rules:
-// 1. The type with the larger maximum exponent always takes precedence.
-// 2. The resulting type must be promoted to at least an int.
-// The following template specializations implement that promotion logic.
-enum ArithmeticPromotionCategory {
-  LEFT_PROMOTION,
-  RIGHT_PROMOTION,
-  DEFAULT_PROMOTION
-};
-
-template <typename Lhs,
-          typename Rhs = Lhs,
-          ArithmeticPromotionCategory Promotion =
-              (MaxExponent<Lhs>::value > MaxExponent<Rhs>::value)
-                  ? (MaxExponent<Lhs>::value > MaxExponent<int>::value
-                         ? LEFT_PROMOTION
-                         : DEFAULT_PROMOTION)
-                  : (MaxExponent<Rhs>::value > MaxExponent<int>::value
-                         ? RIGHT_PROMOTION
-                         : DEFAULT_PROMOTION) >
-struct ArithmeticPromotion;
-
-template <typename Lhs, typename Rhs>
-struct ArithmeticPromotion<Lhs, Rhs, LEFT_PROMOTION> {
-  typedef Lhs type;
-};
-
-template <typename Lhs, typename Rhs>
-struct ArithmeticPromotion<Lhs, Rhs, RIGHT_PROMOTION> {
-  typedef Rhs type;
-};
-
-template <typename Lhs, typename Rhs>
-struct ArithmeticPromotion<Lhs, Rhs, DEFAULT_PROMOTION> {
-  typedef int type;
-};
-
-// We can statically check if operations on the provided types can wrap, so we
-// can skip the checked operations if they're not needed. So, for an integer we
-// care if the destination type preserves the sign and is twice the width of
-// the source.
-template <typename T, typename Lhs, typename Rhs>
-struct IsIntegerArithmeticSafe {
-  static const bool value = !std::numeric_limits<T>::is_iec559 &&
-                            StaticDstRangeRelationToSrcRange<T, Lhs>::value ==
-                                NUMERIC_RANGE_CONTAINED &&
-                            sizeof(T) >= (2 * sizeof(Lhs)) &&
-                            StaticDstRangeRelationToSrcRange<T, Rhs>::value !=
-                                NUMERIC_RANGE_CONTAINED &&
-                            sizeof(T) >= (2 * sizeof(Rhs));
-};
-
-}  // namespace internal
-}  // namespace base
-
-#endif  // SAFE_MATH_IMPL_H_
diff --git a/third_party/template_util.h b/third_party/template_util.h
deleted file mode 100644
index d4508dd696..0000000000
--- a/third_party/template_util.h
+++ /dev/null
@@ -1,33 +0,0 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef BASE_TEMPLATE_UTIL_H_
-#define BASE_TEMPLATE_UTIL_H_
-
-#include <cstddef>  // For size_t.
-
-namespace base {
-
-template<class T, T v>
-struct integral_constant {
-  static const T value = v;
-  typedef T value_type;
-  typedef integral_constant<T, v> type;
-};
-
-typedef integral_constant<bool, true> true_type;
-typedef integral_constant<bool, false> false_type;
-
-template <class T, class U> struct is_same : public false_type {};
-template <class T> struct is_same<T,T> : true_type {};
-
-template<bool B, class T = void>
-struct enable_if {};
-
-template<class T>
-struct enable_if<true, T> { typedef T type; };
-
-}  // namespace base
-
-#endif  // BASE_TEMPLATE_UTIL_H_