Rewrite scoped_ptr<T>(NULL) to use the default ctor in remoting/.

remoting/host/input_injector_linux.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 "remoting/host/input_injector.h"
 
 #include <X11/Xlib.h>
 #include <X11/extensions/XTest.h>
 #include <X11/extensions/XInput.h>
 
@@ skipping 482 matching lines @@
 }
 
 }  // namespace
 
 scoped_ptr<InputInjector> InputInjector::Create(
     scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
     scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner) {
   scoped_ptr<InputInjectorLinux> injector(
       new InputInjectorLinux(main_task_runner));
   if (!injector->Init())
-    return scoped_ptr<InputInjector>(NULL);
+    return scoped_ptr<InputInjector>();
   return injector.PassAs<InputInjector>();
 }
 
 }  // namespace remoting