Getting rid of GetDefaultProfile & fixing multi user issues with accessibility

ash/session_state_observer.h

Index: ash/session_state_observer.h
diff --git a/ash/session_state_observer.h b/ash/session_state_observer.h
index 1de31cd1db72b0e6ef1ff54ec7447804ff921a8e..de1b5333801e51934884c9f447da2b23db25d12c 100644
--- a/ash/session_state_observer.h
+++ b/ash/session_state_observer.h
@@ -8,6 +8,7 @@
 #include <string>
 
 #include "ash/ash_export.h"
+#include "base/basictypes.h"
 
 namespace ash {
 
@@ -23,6 +24,19 @@ class ASH_EXPORT SessionStateObserver {
   virtual ~SessionStateObserver() {}
 };
 
+// A class to attach / detach an object as a session state observer with a
+// scoped pointer.
+class ASH_EXPORT ScopedSessionStateObserver {
+ public:
+  explicit ScopedSessionStateObserver(ash::SessionStateObserver* observer);
+  virtual ~ScopedSessionStateObserver();
+
+ private:
+  ash::SessionStateObserver* observer_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedSessionStateObserver);
+};
+
 }  // namespace ash
 
 #endif  // ASH_SESSION_STATE_OBSERVER_H_