Make virtual keyboard work on supervised user creation

ash/shell.cc

Index: ash/shell.cc
diff --git a/ash/shell.cc b/ash/shell.cc
index 8cdfec9c861977a5c88ca323d51d7546de3f1125..4c77fe9f9ebcf45c53f2ab0a81fbdeb4b1f03f07 100644
--- a/ash/shell.cc
+++ b/ash/shell.cc
@@ -1215,12 +1215,23 @@ void Shell::OnSessionStateChanged(session_manager::SessionState state) {
   // multiple times (e.g. initial login vs. multiprofile add session).
   if (state == session_manager::SessionState::ACTIVE) {
     CreateShelfView();
+  }
 
+  // The keyboard is recreated on user profile change, so to refresh keyboard
+  // extensions with the new profile and proper IME engine is called from them.
+  // |LOGGED_IN_NOT_ACTIVE| is needed so that the virtual keyboard works on
+  // supervised user creation. crbug.com/712873
+  // The previous state is checked to avoid needless |CreateKeyboard| call.
+  if ((state == session_manager::SessionState::LOGGED_IN_NOT_ACTIVE ||
+       state == session_manager::SessionState::ACTIVE) &&
+      !(previous_state_ ==
+            session_manager::SessionState::LOGGED_IN_NOT_ACTIVE ||
+        previous_state_ == session_manager::SessionState::ACTIVE)) {

[xiyuan, 2017/05/12 17:30:03]

How about using KeyboardController::GetInstance() to suppress duplicate calls
instead of using a |previous_state_|?

e.g.

  if ((state == SessionState::LOGGED_IN_NOT_ACTIVE ||
       state == SessionState::ACTIVE) &&
       keyboard::IsKeyboardEnabled()) &&
       !KeyboardController::GetInstance()) {
  }

[oka, 2017/06/07 12:42:37]

Updated.

     if (GetAshConfig() != Config::MASH) {

[Alexander Alekseev, 2017/05/12 04:05:21]

Did you verify that multiprofile mode works with this change?

[oka, 2017/06/07 12:42:37]

I manually confirmed keyboard works after multiprofile switch.

-      // Recreate the keyboard after initial login and after multiprofile login.
       CreateKeyboard();
     }
   }
+  previous_state_ = state;
 }
 
 void Shell::OnLoginStatusChanged(LoginStatus login_status) {