Change for building font cache into separate thread inside utility process.

chrome/utility/font_cache_handler_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 CHROME_UTILITY_FONT_CACHE_HANDLER_WIN_H_
 #define CHROME_UTILITY_FONT_CACHE_HANDLER_WIN_H_
 
 #include "base/files/file_path.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
 #include "chrome/utility/utility_message_handler.h"
 
+namespace base {
+class TaskRunner;
+class Thread;
+}
+
 // Handles requests to build a static direct write font cache. Must be invoked
 // in a non-sandboxed utility process. We build static font cache in utility
 // process as it is time consuming as well as crash prone thing. We already
 // have fall back of loading fonts from system fonts directory in place, so even
 // if we fail to build static cache in utility process, chrome will still
 // continue to run as is.
 class FontCacheHandler : public UtilityMessageHandler {
  public:
   FontCacheHandler() {}
   virtual ~FontCacheHandler() {}
 
   // IPC::Listener implementation
   virtual bool OnMessageReceived(const IPC::Message& message) override;
 
  private:
   void OnBuildFontCache(const base::FilePath& full_path);
+  void StartBuildingFontCache(const base::FilePath& full_path);
+  void Cleanup();
+
+  scoped_refptr<base::TaskRunner> utility_task_runner_;
+
+  // Thread that caching process runs on, while FontCacheHandler handles
+  // messages from the browser process.
+  scoped_ptr<base::Thread> cache_thread_;
 
   DISALLOW_COPY_AND_ASSIGN(FontCacheHandler);
 };
 
 #endif  // CHROME_UTILITY_FONT_CACHE_HANDLER_WIN_H_