[session_manager] Move user session initialization code out of ExistingUserController

chrome/browser/chromeos/login/user_flow.cc

Index: chrome/browser/chromeos/login/user_flow.cc
diff --git a/chrome/browser/chromeos/login/user_flow.cc b/chrome/browser/chromeos/login/user_flow.cc
index ffec4623486562cf32ff53a1deb51748e09a8c78..289522f3764cf66697d5bbdd731e8cbba5b2916b 100644
--- a/chrome/browser/chromeos/login/user_flow.cc
+++ b/chrome/browser/chromeos/login/user_flow.cc
@@ -24,6 +24,9 @@ UserFlow::~UserFlow() {}
 
 DefaultUserFlow::~DefaultUserFlow() {}
 
+void DefaultUserFlow::AppendAdditionalCommandLineSwitches() {
+}
+
 bool DefaultUserFlow::CanLockScreen() {
   return true;
 }
@@ -68,10 +71,17 @@ ExtendedUserFlow::ExtendedUserFlow(const std::string& user_id)
 ExtendedUserFlow::~ExtendedUserFlow() {
 }
 
+void ExtendedUserFlow::AppendAdditionalCommandLineSwitches() {
+}
+
 bool ExtendedUserFlow::ShouldShowSettings() {
   return true;
 }
 
+void ExtendedUserFlow::HandleOAuthTokenStatusChange(
+    user_manager::User::OAuthTokenStatus status) {
+}
+
 void ExtendedUserFlow::UnregisterFlowSoon() {
   std::string id_copy(user_id());
   base::MessageLoop::current()->PostTask(FROM_HERE,