[NaCl SDK] Consistent use of copyright header.

native_client_sdk/src/libraries/nacl_io_test/kernel_proxy_mock.cc

-/* Copyright (c) 2012 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.
- */
+// Copyright (c) 2012 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.
 
 #include "kernel_proxy_mock.h"
 #include "nacl_io/kernel_intercept.h"
 
 KernelProxyMock::KernelProxyMock() {}
 
 KernelProxyMock::~KernelProxyMock() {
   // Uninitialize the kernel proxy so wrapped functions passthrough to their
   // unwrapped versions.
   ki_uninit();
 }