Reland: Refactor code that defers extension background page loading

chrome/chrome_browser_extensions.gypi

 # 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.
 
 {
   'variables': {
     # These variables are shared with the GN build.
     # Name is that these are the extensions files for the extensions target.
     # "chrome_browser_extensions_sources' are the extensions files in the
     # browser target.
@@ skipping 29 matching lines @@
       'browser/extensions/chrome_component_extension_resource_manager.cc',
       'browser/extensions/chrome_component_extension_resource_manager.h',
       'browser/extensions/chrome_extension_function.cc',
       'browser/extensions/chrome_extension_function.h',
       'browser/extensions/chrome_extension_host_delegate.cc',
       'browser/extensions/chrome_extension_host_delegate.h',
       'browser/extensions/chrome_extensions_browser_client.cc',
       'browser/extensions/chrome_extensions_browser_client.h',
       'browser/extensions/chrome_notification_observer.cc',
       'browser/extensions/chrome_notification_observer.h',
+      'browser/extensions/chrome_process_manager_delegate.cc',
+      'browser/extensions/chrome_process_manager_delegate.h',
       'browser/extensions/component_loader.cc',
       'browser/extensions/component_loader.h',
       'browser/extensions/context_menu_matcher.cc',
       'browser/extensions/context_menu_matcher.h',
       'browser/extensions/convert_user_script.cc',
       'browser/extensions/convert_user_script.h',
       'browser/extensions/convert_web_app.cc',
       'browser/extensions/convert_web_app.h',
       'browser/extensions/crx_installer.cc',
       'browser/extensions/crx_installer.h',
@@ skipping 1148 matching lines @@
       'type': 'static_library',
       'sources': [ 'browser/extensions/api/cast_channel/cast_channel.proto' ],
       'variables': {
           'proto_in_dir': 'browser/extensions/api/cast_channel',
           'proto_out_dir': 'chrome/browser/extensions/api/cast_channel',
       },
       'includes': [ '../build/protoc.gypi' ]
     },
   ],
 }