Remove Windows XP SHA-256 and ECDSA logic.

net/cert/sha256_legacy_support_win.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 NET_CERT_SHA256_LEGACY_SUPPORT_WIN_H_
-#define NET_CERT_SHA256_LEGACY_SUPPORT_WIN_H_
-
-#include <windows.h>
-
-#include "base/strings/string_piece.h"
-#include "crypto/wincrypt_shim.h"
-#include "net/base/net_export.h"
-
-namespace net {
-
-namespace sha256_interception {
-
-typedef BOOL (WINAPI* CryptVerifyCertificateSignatureExFunc)(
-    HCRYPTPROV_LEGACY provider,
-    DWORD encoding_type,
-    DWORD subject_type,
-    void* subject_data,
-    DWORD issuer_type,
-    void* issuer_data,
-    DWORD flags,
-    void* extra);
-
-// Interception function meant to be called whenever
-// CryptVerifyCertificateSignatureEx is called. Note that the calling
-// conventions do not match, as the caller is expected to ensure that their
-// interposed function handles the calling conventions and provides a pointer
-// to the original CryptVerifyCertificateSignatureEx (e.g. to handle parameters
-// and keys that are not supported).
-NET_EXPORT BOOL CryptVerifyCertificateSignatureExHook(
-    CryptVerifyCertificateSignatureExFunc original_func,
-    HCRYPTPROV_LEGACY provider,
-    DWORD encoding_type,
-    DWORD subject_type,
-    void* subject_data,
-    DWORD issuer_type,
-    void* issuer_data,
-    DWORD flags,
-    void* extra);
-
-}  // namespace sha256_interception
-
-}  // namespace net
-
-#endif  // NET_CERT_SHA256_LEGACY_SUPPORT_WIN_H_