[GCM] Extracting GCMConnectionObserver from GCMAppHandler

components/gcm_driver/gcm_driver_desktop.cc

 // Copyright 2014 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 "components/gcm_driver/gcm_driver_desktop.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/files/file_path.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/sequenced_task_runner.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "components/gcm_driver/gcm_app_handler.h"
 #include "components/gcm_driver/gcm_client_factory.h"
 #include "components/gcm_driver/system_encryptor.h"
 #include "google_apis/gcm/engine/account_mapping.h"
 #include "net/base/ip_endpoint.h"
 #include "net/url_request/url_request_context_getter.h"
 
 namespace gcm {
 
-namespace {
-
-// Empty string is reserved for the default app handler.
-const char kDefaultAppHandler[] = "";
-
-}  // namespace
-
 // Helper class to save tasks to run until we're ready to execute them.
 class GCMDriverDesktop::DelayedTaskController {
  public:
   DelayedTaskController();
   ~DelayedTaskController();
 
   // Adds a task that will be invoked once we're ready.
   void AddTask(const base::Closure& task);
 
   // Sets ready status. It is ready only when check-in is completed and
@@ skipping 414 matching lines @@
 
 void GCMDriverDesktop::RemoveAppHandler(const std::string& app_id) {
   DCHECK(ui_thread_->RunsTasksOnCurrentThread());
   GCMDriver::RemoveAppHandler(app_id);
 
   // Stops the GCM service when no app intends to consume it.
   if (app_handlers().empty())
     Stop();
 }
 
+void GCMDriverDesktop::AddConnectionObserver(GCMConnectionObserver* observer) {
+  connection_observer_list_.AddObserver(observer);
+}
+
+void GCMDriverDesktop::RemoveConnectionObserver(
+    GCMConnectionObserver* observer) {
+  connection_observer_list_.RemoveObserver(observer);
+}
+
 void GCMDriverDesktop::Enable() {
   DCHECK(ui_thread_->RunsTasksOnCurrentThread());
 
   if (gcm_enabled_)
     return;
   gcm_enabled_ = true;
 
   EnsureStarted();
 }
 
@@ skipping 276 matching lines @@
 
 void GCMDriverDesktop::OnConnected(const net::IPEndPoint& ip_endpoint) {
   DCHECK(ui_thread_->RunsTasksOnCurrentThread());
 
   connected_ = true;
 
   // Drop the event if the service has been stopped.
   if (!gcm_started_)
     return;
 
-  const GCMAppHandlerMap& app_handler_map = app_handlers();
-  for (GCMAppHandlerMap::const_iterator iter = app_handler_map.begin();
-       iter != app_handler_map.end(); ++iter) {
-    iter->second->OnConnected(ip_endpoint);
-  }
-
-  GetAppHandler(kDefaultAppHandler)->OnConnected(ip_endpoint);
+  FOR_EACH_OBSERVER(GCMConnectionObserver,
+                    connection_observer_list_,
+                    OnConnected(ip_endpoint));
 }
 
 void GCMDriverDesktop::OnDisconnected() {
   DCHECK(ui_thread_->RunsTasksOnCurrentThread());
 
   connected_ = false;
 
   // Drop the event if the service has been stopped.
   if (!gcm_started_)
     return;
 
-  const GCMAppHandlerMap& app_handler_map = app_handlers();
-  for (GCMAppHandlerMap::const_iterator iter = app_handler_map.begin();
-       iter != app_handler_map.end(); ++iter) {
-    iter->second->OnDisconnected();
-  }
-
-  GetAppHandler(kDefaultAppHandler)->OnDisconnected();
+  FOR_EACH_OBSERVER(
+      GCMConnectionObserver, connection_observer_list_, OnDisconnected());
 }
 
 void GCMDriverDesktop::GetGCMStatisticsFinished(
     const GCMClient::GCMStatistics& stats) {
   DCHECK(ui_thread_->RunsTasksOnCurrentThread());
 
   // Normally request_gcm_statistics_callback_ would not be null.
   if (!request_gcm_statistics_callback_.is_null())
     request_gcm_statistics_callback_.Run(stats);
   else
     LOG(WARNING) << "request_gcm_statistics_callback_ is NULL.";
 }
 
 }  // namespace gcm