OAuth2LoginManager+MergeSessionThrottle hardening, multi-profle support

chrome/browser/chromeos/login/user_manager.cc

Index: chrome/browser/chromeos/login/user_manager.cc
diff --git a/chrome/browser/chromeos/login/user_manager.cc b/chrome/browser/chromeos/login/user_manager.cc
index c0e427d4aaabe1f80d3954fb3d721da4bb2fc5ee..161a38fe81285247842de87fea8e700b6f43dda3 100644
--- a/chrome/browser/chromeos/login/user_manager.cc
+++ b/chrome/browser/chromeos/login/user_manager.cc
@@ -31,9 +31,6 @@ UserManager::Observer::~Observer() {
 void UserManager::Observer::LocalStateChanged(UserManager* user_manager) {
 }
 
-void UserManager::Observer::MergeSessionStateChanged(MergeSessionState state) {
-}
-
 void UserManager::UserSessionStateObserver::ActiveUserChanged(
     const User* active_user) {
 }