Fix unused private field errors in components/nacl/.

components/nacl/loader/nacl_main_platform_delegate_mac.mm

 // Copyright 2013 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 "components/nacl/loader/nacl_main_platform_delegate.h"
 
 #import <Cocoa/Cocoa.h>
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "components/nacl/common/nacl_sandbox_type.h"
 #include "components/nacl/common/nacl_switches.h"
 #include "content/public/common/sandbox_init.h"
 
 NaClMainPlatformDelegate::NaClMainPlatformDelegate(
-    const content::MainFunctionParams& parameters)
-    : parameters_(parameters) {
+    const content::MainFunctionParams& parameters) {
 }
 
 NaClMainPlatformDelegate::~NaClMainPlatformDelegate() {
 }
 
 void NaClMainPlatformDelegate::EnableSandbox() {
   CHECK(content::InitializeSandbox(NACL_SANDBOX_TYPE_NACL_LOADER,
                                    base::FilePath()))
       << "Error initializing sandbox for " << switches::kNaClLoaderProcess;
 }