Remove unused ImmediateShutdownAndExitProcess()

content/content_browser.gypi

 # 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.
 
 {
   'dependencies': [
     '../base/base.gyp:base_static',
     '../crypto/crypto.gyp:crypto',
     '../device/battery/battery.gyp:device_battery',
     '../device/battery/battery.gyp:device_battery_mojo_bindings',
@@ skipping 72 matching lines @@
       'public/browser/browser_main_parts.cc',
       'public/browser/browser_main_parts.h',
       'public/browser/browser_main_runner.h',
       'public/browser/browser_message_filter.cc',
       'public/browser/browser_message_filter.h',
       'public/browser/browser_plugin_guest_delegate.cc',
       'public/browser/browser_plugin_guest_delegate.h',
       'public/browser/browser_plugin_guest_manager.cc',
       'public/browser/browser_plugin_guest_manager.h',
       'public/browser/browser_ppapi_host.h',
-      'public/browser/browser_shutdown.h',
       'public/browser/browser_thread.h',
       'public/browser/browser_thread_delegate.h',
       'public/browser/browser_url_handler.h',
       'public/browser/cert_store.h',
       'public/browser/certificate_request_result_type.h',
       'public/browser/child_process_data.h',
       'public/browser/child_process_security_policy.h',
       'public/browser/client_certificate_delegate.h',
       'public/browser/color_chooser.h',
       'public/browser/content_browser_client.cc',
@@ skipping 1934 matching lines @@
         'browser/media/media_web_contents_observer.h',
       ],
     }],
     ['OS == "linux" and use_openssl==1', {
       'dependencies': [
         '../third_party/boringssl/boringssl.gyp:boringssl',
       ],
     }],
   ],
 }