Remove #pragma once from content

content/browser/android/content_startup_flags.h

 // 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.
 
 #ifndef CONTENT_BROWSER_ANDROID_CONTENT_STARTUP_FLAGS_H_
 #define CONTENT_BROWSER_ANDROID_CONTENT_STARTUP_FLAGS_H_
-#pragma once
 
 #include <string>
 
 namespace content {
 
 // Force-appends flags to the command line turning on Android-specific
 // features owned by Content. This is called as soon as possible during
 // initialization to make sure code sees the new flags.
 void SetContentCommandLineFlags(int max_render_process_count,
                                 const std::string& plugin_descriptor);
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_ANDROID_CONTENT_STARTUP_FLAGS_H_