Remove Windows Vista/XP specific code from net/cert and net/ssl.

net/ssl/ssl_platform_key_win.cc

Index: net/ssl/ssl_platform_key_win.cc
diff --git a/net/ssl/ssl_platform_key_win.cc b/net/ssl/ssl_platform_key_win.cc
index d49d72f25f8ed311b5811a5fa887c42a36d7a8b1..11c9d111a3d0d7bef3a5e950db77225ad18b6337 100644
--- a/net/ssl/ssl_platform_key_win.cc
+++ b/net/ssl/ssl_platform_key_win.cc
@@ -21,7 +21,6 @@
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/sequenced_task_runner.h"
-#include "base/win/windows_version.h"
 #include "crypto/openssl_util.h"
 #include "crypto/scoped_capi_types.h"
 #include "crypto/wincrypt_shim.h"
@@ -337,9 +336,7 @@ scoped_refptr<SSLPrivateKey> FetchClientCertPrivateKey(
   HCRYPTPROV_OR_NCRYPT_KEY_HANDLE prov_or_key = 0;
   DWORD key_spec = 0;
   BOOL must_free = FALSE;
-  DWORD flags = 0;
-  if (base::win::GetVersion() >= base::win::VERSION_VISTA)
-    flags |= CRYPT_ACQUIRE_PREFER_NCRYPT_KEY_FLAG;
+  DWORD flags = CRYPT_ACQUIRE_PREFER_NCRYPT_KEY_FLAG;
 
   if (!CryptAcquireCertificatePrivateKey(cert_context, flags, nullptr,
                                          &prov_or_key, &key_spec, &must_free)) {