ash: Use SessionController instead of SessionStateDelegate

ash/common/session/session_controller.cc

Index: ash/common/session/session_controller.cc
diff --git a/ash/common/session/session_controller.cc b/ash/common/session/session_controller.cc
index 12a9cec3b659a199a4d56921e3e032266f8adaa2..27f130a13eab06a7c2ddc2cdfe43e6657439d38f 100644
--- a/ash/common/session/session_controller.cc
+++ b/ash/common/session/session_controller.cc
@@ -40,7 +40,7 @@ bool SessionController::IsActiveUserSessionStarted() const {
 }
 
 bool SessionController::CanLockScreen() const {
-  return can_lock_;
+  return IsActiveUserSessionStarted() && can_lock_;

[xiyuan, 2017/03/17 07:08:15]

Behavior change, caught by LockStateControllerTest.LockButtonBasicNotLoggedIn.
Chrome side SessionControllerClient guarantees that but we were not enforcing it
here in ash.

 }
 
 bool SessionController::IsScreenLocked() const {
@@ -55,6 +55,10 @@ bool SessionController::IsUserSessionBlocked() const {
   return state_ != session_manager::SessionState::ACTIVE;
 }
 
+bool SessionController::IsInSecondaryLoginScreen() const {
+  return state_ == session_manager::SessionState::LOGIN_SECONDARY;
+}
+
 session_manager::SessionState SessionController::GetSessionState() const {
   return state_;
 }
@@ -64,6 +68,14 @@ const std::vector<mojom::UserSessionPtr>& SessionController::GetUserSessions()
   return user_sessions_;
 }
 
+const mojom::UserSession* SessionController::GetUserSession(
+    UserIndex index) const {
+  if (index < 0 || index >= static_cast<UserIndex>(user_sessions_.size()))
+    return nullptr;
+
+  return user_sessions_[index].get();
+}
+
 void SessionController::LockScreen() {
   if (client_)
     client_->RequestLockScreen();
@@ -172,6 +184,15 @@ void SessionController::SetUserSessionOrder(
   }
 }
 
+void SessionController::ClearUserSessionsForTest() {
+  user_sessions_.clear();
+}
+
+void SessionController::LockScreenAndFlushForTest() {
+  LockScreen();
+  client_.FlushForTesting();
+}
+
 void SessionController::SetSessionState(session_manager::SessionState state) {
   if (state_ == state)
     return;