Just some cleanup before I start on the profile name fix.

chrome/browser/profiles/gaia_info_update_service.cc

Index: chrome/browser/profiles/gaia_info_update_service.cc
diff --git a/chrome/browser/profiles/gaia_info_update_service.cc b/chrome/browser/profiles/gaia_info_update_service.cc
index 9585110d5637372a89b3ccf6ab795facf100178b..d953cf211acd06bcd1ba2dd93900c11e41d8cf44 100644
--- a/chrome/browser/profiles/gaia_info_update_service.cc
+++ b/chrome/browser/profiles/gaia_info_update_service.cc
@@ -10,6 +10,7 @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_info_cache.h"
 #include "chrome/browser/profiles/profile_manager.h"
+#include "chrome/browser/signin/signin_manager_factory.h"
 #include "chrome/browser/sync/profile_sync_service.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/profile_management_switches.h"
@@ -30,24 +31,25 @@ const int kMinUpdateIntervalSeconds = 5;
 
 GAIAInfoUpdateService::GAIAInfoUpdateService(Profile* profile)
     : profile_(profile) {
-  PrefService* prefs = profile_->GetPrefs();
-  username_pref_.Init(prefs::kGoogleServicesUsername, prefs,
-                      base::Bind(&GAIAInfoUpdateService::OnUsernameChanged,
-                                 base::Unretained(this)));
+  SigninManagerBase* signin_manager =
+      SigninManagerFactory::GetForProfile(profile_);
+  signin_manager->AddObserver(this);
 
+  PrefService* prefs = profile_->GetPrefs();
   last_updated_ = base::Time::FromInternalValue(
       prefs->GetInt64(prefs::kProfileGAIAInfoUpdateTime));
   ScheduleNextUpdate();
 }
 
 GAIAInfoUpdateService::~GAIAInfoUpdateService() {
+  DCHECK(!profile_) << "Shutdown not called before dtor";
 }
 
 void GAIAInfoUpdateService::Update() {
   // The user must be logged in.
-  std::string username = profile_->GetPrefs()->GetString(
-      prefs::kGoogleServicesUsername);
-  if (username.empty())
+  SigninManagerBase* signin_manager =
+      SigninManagerFactory::GetForProfile(profile_);
+  if (signin_manager->GetAuthenticatedAccountId().empty())
     return;
 
   if (profile_image_downloader_)
@@ -151,15 +153,13 @@ void GAIAInfoUpdateService::OnProfileDownloadFailure(
   ScheduleNextUpdate();
 }
 
-void GAIAInfoUpdateService::OnUsernameChanged() {
+void GAIAInfoUpdateService::OnUsernameChanged(const std::string& username) {
   ProfileInfoCache& cache =
       g_browser_process->profile_manager()->GetProfileInfoCache();
   size_t profile_index = cache.GetIndexOfProfileWithPath(profile_->GetPath());
   if (profile_index == std::string::npos)
     return;
 
-  std::string username = profile_->GetPrefs()->GetString(
-      prefs::kGoogleServicesUsername);
   if (username.empty()) {
     // Unset the old user's GAIA info.
     cache.SetGAIANameOfProfileAtIndex(profile_index, base::string16());
@@ -176,6 +176,14 @@ void GAIAInfoUpdateService::OnUsernameChanged() {
   }
 }
 
+void GAIAInfoUpdateService::Shutdown() {
+  SigninManagerBase* signin_manager =
+      SigninManagerFactory::GetForProfile(profile_);
+  profile_image_downloader_.reset();
+  signin_manager->RemoveObserver(this);
+  profile_ = NULL;

[noms (inactive), 2014/03/24 13:35:25]

Can you maybe add a comment as yo why it's ok to null out this pointer, as we
don't normally null out Profile pointers...

[Roger Tawa OOO till Jul 10th, 2014/03/24 17:49:30]

Done.

+}
+
 void GAIAInfoUpdateService::ScheduleNextUpdate() {
   if (timer_.IsRunning())
     return;
@@ -192,3 +200,13 @@ void GAIAInfoUpdateService::ScheduleNextUpdate() {
 
   timer_.Start(FROM_HERE, delta, this, &GAIAInfoUpdateService::Update);
 }
+
+void GAIAInfoUpdateService::GoogleSigninSucceeded(
+    const std::string& username,
+    const std::string& password) {
+  OnUsernameChanged(username);
+}
+
+void GAIAInfoUpdateService::GoogleSignedOut(const std::string& username) {
+  OnUsernameChanged(std::string());
+}