Introduce NetworkDelegate's implementation in extensions.

extensions/extensions.gyp

 # Copyright 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': {
     'chromium_code': 1,
   },
   'targets': [
     {
@@ skipping 558 matching lines @@
         'browser/extension_function_dispatcher.cc',
         'browser/extension_function_dispatcher.h',
         'browser/extension_function_registry.cc',
         'browser/extension_function_registry.h',
         'browser/extension_function_util.cc',
         'browser/extension_function_util.h',
         'browser/extension_icon_image.cc',
         'browser/extension_icon_image.h',
         'browser/extension_message_filter.cc',
         'browser/extension_message_filter.h',
+        'browser/extension_network_delegate.cc',
+        'browser/extension_network_delegate.h',
         'browser/extension_pref_store.cc',
         'browser/extension_pref_store.h',
         'browser/extension_pref_value_map.cc',
         'browser/extension_pref_value_map_factory.cc',
         'browser/extension_pref_value_map_factory.h',
         'browser/extension_pref_value_map.h',
         'browser/extension_prefs.cc',
         'browser/extension_prefs.h',
         'browser/extension_prefs_factory.cc',
         'browser/extension_prefs_factory.h',
         'browser/extension_prefs_observer.h',
         'browser/extension_prefs_scope.h',
         'browser/extension_protocols.cc',
         'browser/extension_protocols.h',
         'browser/extension_registry.cc',
         'browser/extension_registry.h',
         'browser/extension_registry_factory.cc',
         'browser/extension_registry_factory.h',
         'browser/extension_registry_observer.h',
         'browser/extension_scoped_prefs.h',
         'browser/extension_system.cc',
         'browser/extension_system.h',
         'browser/extension_system_provider.cc',
         'browser/extension_system_provider.h',
+        'browser/extension_url_request_context_getter.cc',
+        'browser/extension_url_request_context_getter.h',
         'browser/extension_util.cc',
         'browser/extension_util.h',
         'browser/extension_web_contents_observer.cc',
         'browser/extension_web_contents_observer.h',
         'browser/extensions_browser_client.cc',
         'browser/extensions_browser_client.h',
         'browser/external_provider_interface.h',
         'browser/granted_file_entry.cc',
         'browser/granted_file_entry.h',
         'browser/guest_view/app_view/app_view_constants.cc',
@@ skipping 559 matching lines @@
       'conditions': [
         ['OS=="win" and win_use_allocator_shim==1', {
           'dependencies': [
             '../base/allocator/allocator.gyp:allocator',
           ],
         }],
       ],
     },
   ]
 }