Use a NotificationRegistrar to listen for notifications.

BUG=2381
Review URL: http://codereview.chromium.org/114040

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@16792 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 37 insertions, 52 deletions

diff --git a/chrome/browser/metrics/metrics_service.cc b/chrome/browser/metrics/metrics_service.cc
index 21adc52..0289dd8 100644
--- a/chrome/browser/metrics/metrics_service.cc
+++ b/chrome/browser/metrics/metrics_service.cc
@@ -443,10 +443,41 @@ void MetricsService::SetRecording(bool enabled) {
       }
     }
     StartRecording();
-    ListenerRegistration(true);
+
+    registrar_.Add(this, NotificationType::BROWSER_OPENED,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::BROWSER_CLOSED,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::USER_ACTION,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::TAB_PARENTED,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::TAB_CLOSING,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::LOAD_START,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::LOAD_STOP,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::RENDERER_PROCESS_IN_SBOX,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::RENDERER_PROCESS_CLOSED,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::RENDERER_PROCESS_HANG,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::CHILD_PROCESS_HOST_CONNECTED,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::CHILD_INSTANCE_CREATED,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::CHILD_PROCESS_CRASHED,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::TEMPLATE_URL_MODEL_LOADED,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::OMNIBOX_OPENED_URL,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::BOOKMARK_MODEL_LOADED,
+                   NotificationService::AllSources());
   } else {
-    // Turn off all observers.
-    ListenerRegistration(false);
+    registrar_.RemoveAll();
     PushPendingLogsToUnsentLists();
     DCHECK(!pending_log());
     if (state_ > INITIAL_LOG_READY && unsent_logs())
@@ -787,46 +818,6 @@ void MetricsService::StopRecording(MetricsLog** log) {
   current_log_ = NULL;
 }
 
-void MetricsService::ListenerRegistration(bool start_listening) {
-  AddOrRemoveObserver(this, NotificationType::BROWSER_OPENED, start_listening);
-  AddOrRemoveObserver(this, NotificationType::BROWSER_CLOSED, start_listening);
-  AddOrRemoveObserver(this, NotificationType::USER_ACTION, start_listening);
-  AddOrRemoveObserver(this, NotificationType::TAB_PARENTED, start_listening);
-  AddOrRemoveObserver(this, NotificationType::TAB_CLOSING, start_listening);
-  AddOrRemoveObserver(this, NotificationType::LOAD_START, start_listening);
-  AddOrRemoveObserver(this, NotificationType::LOAD_STOP, start_listening);
-  AddOrRemoveObserver(this, NotificationType::RENDERER_PROCESS_IN_SBOX,
-                      start_listening);
-  AddOrRemoveObserver(this, NotificationType::RENDERER_PROCESS_CLOSED,
-                      start_listening);
-  AddOrRemoveObserver(this, NotificationType::RENDERER_PROCESS_HANG,
-                      start_listening);
-  AddOrRemoveObserver(this, NotificationType::CHILD_PROCESS_HOST_CONNECTED,
-                      start_listening);
-  AddOrRemoveObserver(this, NotificationType::CHILD_INSTANCE_CREATED,
-                      start_listening);
-  AddOrRemoveObserver(this, NotificationType::CHILD_PROCESS_CRASHED,
-                      start_listening);
-  AddOrRemoveObserver(this, NotificationType::TEMPLATE_URL_MODEL_LOADED,
-                      start_listening);
-  AddOrRemoveObserver(this, NotificationType::OMNIBOX_OPENED_URL,
-                      start_listening);
-  AddOrRemoveObserver(this, NotificationType::BOOKMARK_MODEL_LOADED,
-                      start_listening);
-}
-
-// static
-void MetricsService::AddOrRemoveObserver(NotificationObserver* observer,
-                                         NotificationType type,
-                                         bool is_add) {
-  NotificationService* service = NotificationService::current();
-
-  if (is_add)
-    service->AddObserver(observer, type, NotificationService::AllSources());
-  else
-    service->RemoveObserver(observer, type, NotificationService::AllSources());
-}
-
 void MetricsService::PushPendingLogsToUnsentLists() {
   if (state_ < INITIAL_LOG_READY)
     return;  // We didn't and still don't have time to get plugin list etc.
diff --git a/chrome/browser/metrics/metrics_service.h b/chrome/browser/metrics/metrics_service.h
index 426c66e..199e1b1 100644
--- a/chrome/browser/metrics/metrics_service.h
+++ b/chrome/browser/metrics/metrics_service.h
@@ -20,7 +20,7 @@
 #include "base/values.h"
 #include "chrome/browser/metrics/metrics_log.h"
 #include "chrome/browser/net/url_fetcher.h"
-#include "chrome/common/notification_observer.h"
+#include "chrome/common/notification_registrar.h"
 #include "webkit/glue/webplugin.h"
 
 class BookmarkModel;
@@ -177,14 +177,6 @@ class MetricsService : public NotificationObserver,
   // or passes in NULL to indicate that the log should simply be deleted.
   void StopRecording(MetricsLog** log);
 
-  void ListenerRegistration(bool start_listening);
-
-  // Adds or Removes (depending on the value of is_add) the given observer
-  // to the given notification type for all sources.
-  static void AddOrRemoveObserver(NotificationObserver* observer,
-                                  NotificationType type,
-                                  bool is_add);
-
   // Deletes pending_log_ and current_log_, and pushes their text into the
   // appropriate unsent_log vectors.  Called when Chrome shuts down.
   void PushPendingLogsToUnsentLists();
@@ -377,6 +369,8 @@ class MetricsService : public NotificationObserver,
   // Sets the value of the specified path in prefs and schedules a save.
   void RecordBooleanPrefValue(const wchar_t* path, bool value);
 
+  NotificationRegistrar registrar_;
+
   // Indicate whether recording and reporting are currently happening.
   // These should not be set directly, but by calling SetRecording and
   // SetReporting.