Getting rid of GetDefaultProfile & fixing multi user issues with accessibility

chrome/browser/chromeos/accessibility/magnification_manager.cc

Index: chrome/browser/chromeos/accessibility/magnification_manager.cc
diff --git a/chrome/browser/chromeos/accessibility/magnification_manager.cc b/chrome/browser/chromeos/accessibility/magnification_manager.cc
index 30519080d722aa042dda0d6582f0f27865858209..181484e5cae8445dc9095c2f0f23182b679f399c 100644
--- a/chrome/browser/chromeos/accessibility/magnification_manager.cc
+++ b/chrome/browser/chromeos/accessibility/magnification_manager.cc
@@ -8,6 +8,7 @@
 
 #include "ash/magnifier/magnification_controller.h"
 #include "ash/magnifier/partial_magnification_controller.h"
+#include "ash/session_state_delegate.h"
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
 #include "ash/system/tray/system_tray_notifier.h"
@@ -35,7 +36,8 @@ static MagnificationManager* g_magnification_manager = NULL;
 }
 
 class MagnificationManagerImpl : public MagnificationManager,
-                                 public content::NotificationObserver {
+                                 public content::NotificationObserver,
+                                 public ash::SessionStateObserver {
  public:
   MagnificationManagerImpl()
       : first_time_update_(true),
@@ -105,6 +107,11 @@ class MagnificationManagerImpl : public MagnificationManager,
     SetProfile(profile);
   }
 
+  // SessionStateObserver overrides:
+  virtual void ActiveUserChanged(const std::string& user_id) OVERRIDE {
+    SetProfile(ProfileManager::GetActiveUserProfile());
+  }
+
  private:
   void SetProfile(Profile* profile) {
     pref_change_registrar_.reset();
@@ -209,6 +216,11 @@ class MagnificationManagerImpl : public MagnificationManager,
       case chrome::NOTIFICATION_SESSION_STARTED:
         // Update |profile_| when entering a session.
         SetProfile(ProfileManager::GetDefaultProfile());
+
+        // Add a session state observer to be able to monitor session changes.
+        if (!session_state_observer_.get() && ash::Shell::HasInstance())
+          session_state_observer_.reset(
+              new ash::ScopedSessionStateObserver(this));
         break;
       case chrome::NOTIFICATION_PROFILE_DESTROYED: {
         // Update |profile_| when exiting a session or shutting down.
@@ -229,8 +241,10 @@ class MagnificationManagerImpl : public MagnificationManager,
 
   ash::MagnifierType type_;
   bool enabled_;
+
   content::NotificationRegistrar registrar_;
   scoped_ptr<PrefChangeRegistrar> pref_change_registrar_;
+  scoped_ptr<ash::ScopedSessionStateObserver> session_state_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(MagnificationManagerImpl);
 };