Remove PlatformFile from spell checker

chrome/renderer/spellchecker/cocoa_spelling_engine_mac.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.
 
 #include "cocoa_spelling_engine_mac.h"
 
 #include "chrome/common/spellcheck_messages.h"
 #include "content/public/renderer/render_thread.h"
 
 using content::RenderThread;
 
 SpellingEngine* CreateNativeSpellingEngine() {
   return new CocoaSpellingEngine();
 }
 
-void CocoaSpellingEngine::Init(base::PlatformFile bdict_file) {
-  DCHECK(bdict_file == base::kInvalidPlatformFileValue);
+void CocoaSpellingEngine::Init(base::File bdict_file) {
+  DCHECK(!bdict_file.IsValid());
 }
 
 bool CocoaSpellingEngine::InitializeIfNeeded() {
   return false;  // We never need to initialize.
 }
 
 bool CocoaSpellingEngine::IsEnabled() {
   return true;  // OSX is always enabled.
 }
 
@@ skipping 10 matching lines @@
 
 // Synchronously query against NSSpellCheck.
 // TODO(groby): We might want async support here, too. Ideally,
 // all engines share a similar path for async requests.
 void CocoaSpellingEngine::FillSuggestionList(
     const base::string16& wrong_word,
     std::vector<base::string16>* optional_suggestions) {
     RenderThread::Get()->Send(new SpellCheckHostMsg_FillSuggestionList(
         wrong_word, optional_suggestions));
 }