app_shell: Convert ExtensionsWebContentsObserver to BrowserContext from Profile

chrome/browser/extensions/api/messaging/message_service.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 "chrome/browser/extensions/api/messaging/message_service.h"
 
 #include "base/atomic_sequence_num.h"
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/json/json_writer.h"
@@ skipping 169 matching lines @@
 
 static base::LazyInstance<ProfileKeyedAPIFactory<MessageService> >
 g_factory = LAZY_INSTANCE_INITIALIZER;
 
 // static
 ProfileKeyedAPIFactory<MessageService>* MessageService::GetFactoryInstance() {
   return &g_factory.Get();
 }
 
 // static
-MessageService* MessageService::Get(Profile* profile) {
+MessageService* MessageService::Get(content::BrowserContext* context) {
+  Profile* profile = Profile::FromBrowserContext(context);
   return ProfileKeyedAPIFactory<MessageService>::GetForProfile(profile);
 }
 
 void MessageService::OpenChannelToExtension(
     int source_process_id, int source_routing_id, int receiver_port_id,
     const std::string& source_extension_id,
     const std::string& target_extension_id,
     const GURL& source_url,
     const std::string& channel_name,
     bool include_tls_channel_id) {
@@ skipping 552 matching lines @@
 }
 
 void MessageService::DispatchOnDisconnect(content::RenderProcessHost* source,
                                           int port_id,
                                           const std::string& error_message) {
   ExtensionMessagePort port(source, MSG_ROUTING_CONTROL, "");
   port.DispatchOnDisconnect(GET_OPPOSITE_PORT_ID(port_id), error_message);
 }
 
 }  // namespace extensions