Remove more unnecessary includes, limits.h and climits in base/numerics

base/numerics/safe_conversions_impl.h

 // 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_NUMERICS_SAFE_CONVERSIONS_IMPL_H_
 #define BASE_NUMERICS_SAFE_CONVERSIONS_IMPL_H_
 
-#include <limits.h>
 #include <stdint.h>
 
-#include <climits>
 #include <limits>
 #include <type_traits>
 
 namespace base {
 namespace internal {
 
 // The std library doesn't provide a binary max_exponent for integers, however
 // we can compute an analog using std::numeric_limits<>::digits.
 template <typename NumericType>
 struct MaxExponent {
@@ skipping 587 matching lines @@
                    static_cast<BigType>(static_cast<L>(lhs)),
                    static_cast<BigType>(static_cast<R>(rhs)))
              // Let the template functions figure it out for mixed types.
              : C<L, R>::Test(lhs, rhs);
 };
 
 }  // namespace internal
 }  // namespace base
 
 #endif  // BASE_NUMERICS_SAFE_CONVERSIONS_IMPL_H_