Lazy initialization for PushMessagingEventRouter

chrome/browser/extensions/api/push_messaging/push_messaging_api.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/push_messaging/push_messaging_api.h"
 
 #include <set>
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/string_number_conversions.h"
 #include "base/values.h"
+#include "chrome/browser/extensions/api/push_messaging/push_messaging_api_factory.h"
 #include "chrome/browser/extensions/api/push_messaging/push_messaging_invalidation_handler.h"
 #include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/signin/token_service.h"
 #include "chrome/browser/signin/token_service_factory.h"
 #include "chrome/browser/sync/profile_sync_service.h"
 #include "chrome/browser/sync/profile_sync_service_factory.h"
@@ skipping 260 matching lines @@
   std::string error_text = error.error_message();
   // If the error message is blank, see if we can set it from the state.
   if (error_text.empty() &&
       (0 != error.state())) {
     error_text = base::IntToString(error.state());
   }
 
   ReportResult(std::string(), error_text);
 }
 
+PushMessagingAPI::PushMessagingAPI(Profile* profile)
+    : profile_(profile) {
+  ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
+      this, event_names::kOnPushMessage);
+}
+
+PushMessagingAPI::~PushMessagingAPI() {
+}
+
+// static
+PushMessagingAPI* PushMessagingAPI::Get(Profile* profile) {
+  return PushMessagingAPIFactory::GetForProfile(profile);
+}
+
+PushMessagingEventRouter* PushMessagingAPI::push_messaging_event_router() {
+  if (!push_messaging_event_router_)
+    push_messaging_event_router_.reset(new PushMessagingEventRouter(profile_));
+  return push_messaging_event_router_.get();
+}
+
+void PushMessagingAPI::OnProfileSyncServiceShutdown() {
+  // TODO(akalin): Move this block to Shutdown() once

[Yoyo Zhou, 2012/12/10 20:06:01]

I believe you can do this and get rid of OnProfileSyncServiceShutdown
altogether.

akalin: do you agree?

[akalin, 2012/12/10 20:37:12]

Yeah, per your other comment, I agree.

[Joe Thomas, 2012/12/10 22:43:58]

Done.

+  // http://crbug.com/153827 is fixed.
+  if (push_messaging_event_router_.get())
+    push_messaging_event_router_->Shutdown();
+}
+
+void PushMessagingAPI::Shutdown() {
+  ExtensionSystem::Get(profile_)->event_router()->UnregisterObserver(this);
+}
+
+void PushMessagingAPI::OnListenerAdded(
+    const extensions::EventListenerInfo& details) {
+  push_messaging_event_router();
+  ExtensionSystem::Get(profile_)->event_router()->UnregisterObserver(this);
+}
+
 }  // namespace extensions