Move thread_pool.h into utils so it can be shared by more than one example.

native_client_sdk/src/libraries/ppapi_simple/ps_instance.h

 // Copyright (c) 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.
 
 #ifndef PPAPI_SIMPLE_PS_INSTANCE_H_
 #define PPAPI_SIMPLE_PS_INSTANCE_H_
 
 #include <map>
 
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_stdint.h"
 #include "ppapi/c/ppb_core.h"
 #include "ppapi/c/ppb_var.h"
 #include "ppapi/c/ppb_view.h"
 
 #include "ppapi/cpp/fullscreen.h"
 #include "ppapi/cpp/instance.h"
 #include "ppapi/cpp/message_loop.h"
 #include "ppapi/cpp/mouse_lock.h"
 
 #include "ppapi/utility/completion_callback_factory.h"
 
 #include "ppapi_simple/ps_event.h"
 #include "ppapi_simple/ps_main.h"
 
-#include "utils/thread_safe_queue.h"
+#include "sdk_util/thread_safe_queue.h"
 
 
 typedef std::map<std::string, std::string> PropertyMap_t;
 
 class PSInstance : public pp::Instance {
  public:
   enum Verbosity {
     PSV_SILENT,
     PSV_ERROR,
     PSV_WARN,
@@ skipping 75 matching lines @@
 
   PSMainFunc_t main_cb_;
 
   const PPB_Core* ppb_core_;
   const PPB_Var* ppb_var_;
   const PPB_View* ppb_view_;
 };
 
 #endif  // PPAPI_MAIN_PS_INSTANCE_H_