Lazy initialization for PushMessagingEventRouter

chrome/browser/extensions/api/push_messaging/push_messaging_api.cc

Index: chrome/browser/extensions/api/push_messaging/push_messaging_api.cc
diff --git a/chrome/browser/extensions/api/push_messaging/push_messaging_api.cc b/chrome/browser/extensions/api/push_messaging/push_messaging_api.cc
index d92305af16281e95976783f8079680ab16237206..a8780fc3befd6e5cc36b4211092ef9d8afcca184 100644
--- a/chrome/browser/extensions/api/push_messaging/push_messaging_api.cc
+++ b/chrome/browser/extensions/api/push_messaging/push_messaging_api.cc
@@ -10,6 +10,7 @@
 #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"
@@ -290,4 +291,36 @@ void PushMessagingGetChannelIdFunction::OnObfuscatedGaiaIdFetchFailure(
   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::Shutdown() {
+  ExtensionSystem::Get(profile_)->event_router()->UnregisterObserver(this);
+  if (push_messaging_event_router_.get())
+    push_messaging_event_router_->Shutdown();
+}
+
+void PushMessagingAPI::OnListenerAdded(
+    const extensions::EventListenerInfo& details) {
+  push_messaging_event_router();
+  ExtensionSystem::Get(profile_)->event_router()->UnregisterObserver(this);
+}
+
 }  // namespace extensions