Update the AvatarMenu when a supervised user's custodian info changes.

chrome/browser/profiles/avatar_menu.cc

Index: chrome/browser/profiles/avatar_menu.cc
diff --git a/chrome/browser/profiles/avatar_menu.cc b/chrome/browser/profiles/avatar_menu.cc
index da41957edccb2bd1bd9f0c4525afd2e25e2fc852..ff34373670bba49be07eb8c358cf83106ad97612 100644
--- a/chrome/browser/profiles/avatar_menu.cc
+++ b/chrome/browser/profiles/avatar_menu.cc
@@ -64,9 +64,26 @@ AvatarMenu::AvatarMenu(ProfileInfoInterface* profile_cache,
   // Register this as an observer of the info cache.
   registrar_.Add(this, chrome::NOTIFICATION_PROFILE_CACHED_INFO_CHANGED,
       content::NotificationService::AllSources());
+
+#if defined(ENABLE_MANAGED_USERS)
+  // Register this as an observer of the SupervisedUserService to be notified
+  // of changes to the custodian info.
+  if (browser_) {
+    SupervisedUserService* service =
+        SupervisedUserServiceFactory::GetForProfile(browser_->profile());

[noms (inactive), 2014/09/25 14:22:22]

Is it possible to be in a state where browser_->profile() is the Guest Profile,
for which service might be NULL? 

[Marc Treib, 2014/09/25 14:50:56]

browser_->profile() can be the guest profile, but service still isn't NULL.
Maybe it can be NULL in tests? I haven't checked that yet.

[Bernhard Bauer, 2014/09/25 15:15:48]

Yeah, I don't think we set it to NULL for testing profiles.

+    service->AddObserver(this);
+  }
+#endif
 }
 
 AvatarMenu::~AvatarMenu() {
+#if defined(ENABLE_MANAGED_USERS)
+  if (browser_) {
+    SupervisedUserService* service =
+        SupervisedUserServiceFactory::GetForProfile(browser_->profile());
+    service->RemoveObserver(this);

[Bernhard Bauer, 2014/09/25 15:15:48]

A ScopedObserver might be useful here, to do this automatically at destruction.

[Marc Treib, 2014/09/25 15:30:28]

Done.

+  }
+#endif
 }
 
 AvatarMenu::Item::Item(size_t menu_index,
@@ -234,3 +251,11 @@ void AvatarMenu::Observe(int type,
   if (observer_)
     observer_->OnAvatarMenuChanged(this);
 }
+
+#if defined(ENABLE_MANAGED_USERS)
+void AvatarMenu::OnCustodianInfoChanged() {
+  RebuildMenu();
+  if (observer_)
+    observer_->OnAvatarMenuChanged(this);
+}
+#endif