We should switch the keyboard layout to the layout the user set according to

chrome/browser/chromeos/input_method/input_method_persistence.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/chromeos/input_method/input_method_persistence.h"
 
+#include "base/chromeos/chromeos_version.h"
 #include "base/logging.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/input_method/input_method_util.h"
 #include "chrome/browser/chromeos/language_preferences.h"
+#include "chrome/browser/prefs/scoped_user_pref_update.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/pref_names.h"
 
 namespace chromeos {
 namespace input_method {
 namespace {
 
 void PersistSystemInputMethod(const std::string& input_method) {
   if (!g_browser_process || !g_browser_process->local_state())
     return;
 
   g_browser_process->local_state()->SetString(
         language_prefs::kPreferredKeyboardLayout, input_method);
 }
 
-void PersistUserInputMethod(const std::string& input_method) {
+// Update user LRU keyboard layout for login screen
+static void SetUserLRUInputMethod(
+    const std::string& input_method,
+    const chromeos::input_method::InputMethodManager* const manager) {
+  // Skip if it's not a keyboard layout. Drop input methods including
+  // extension ones.
+  if (!InputMethodUtil::IsKeyboardLayout(input_method))
+    return;
+
+  PrefService* const local_state = g_browser_process->local_state();
+
+  Profile* const profile = ProfileManager::GetDefaultProfile();
+
+  if (profile == NULL)
+    return;
+
+  if (!manager->IsFullLatinKeyboard(input_method))
+    return;
+
+  const std::string username = profile->GetProfileName();
+  if (base::chromeos::IsRunningOnChromeOS() && !username.empty() &&
+      !local_state->ReadOnly()) {
+    bool update_succeed = false;
+    {
+      // Updater may have side-effects, therefore we do not replace
+      // entry while updater exists.
+      DictionaryPrefUpdate updater(local_state, prefs::kUsersLRUInputMethod);
+      base::DictionaryValue* const users_lru_input_methods = updater.Get();
+      if (users_lru_input_methods) {
+        users_lru_input_methods->SetStringWithoutPathExpansion(username,
+                                                               input_method);
+        update_succeed = true;
+      }
+    }
+    if (!update_succeed) {
+      // Somehow key kUsersLRUInputMethod has value of invalid type.
+      // Replace and retry.
+      local_state->Set(prefs::kUsersLRUInputMethod, base::DictionaryValue());
+
+      DictionaryPrefUpdate updater(local_state, prefs::kUsersLRUInputMethod);
+      base::DictionaryValue* const users_lru_input_methods = updater.Get();
+      if (users_lru_input_methods) {
+        users_lru_input_methods->SetStringWithoutPathExpansion(username,
+                                                               input_method);
+        update_succeed = true;
+      }
+    }
+    if (!update_succeed) {
+      DVLOG(1) << "Failed to replace local_state.kUsersLRUInputMethod: '"
+                   << prefs::kUsersLRUInputMethod << "' for '" << username

[Seigo Nonaka, 2013/07/22 13:17:34]

nit: indent?

[Alexander Alekseev, 2013/07/22 14:24:21]

Done.

+                   << "'";
+    }
+  }
+}
+
+void PersistUserInputMethod(const std::string& input_method,
+                            InputMethodManager* const manager) {
   PrefService* user_prefs = NULL;
   Profile* profile = ProfileManager::GetDefaultProfile();
   if (profile)
     user_prefs = profile->GetPrefs();
   if (!user_prefs)
     return;
 
+  SetUserLRUInputMethod(input_method, manager);
+
   const std::string current_input_method_on_pref =
       user_prefs->GetString(prefs::kLanguageCurrentInputMethod);
   if (current_input_method_on_pref == input_method)
     return;
 
   user_prefs->SetString(prefs::kLanguagePreviousInputMethod,
                         current_input_method_on_pref);
   user_prefs->SetString(prefs::kLanguageCurrentInputMethod,
                         input_method);
 }
@@ skipping 20 matching lines @@
   switch (state_) {
     case InputMethodManager::STATE_LOGIN_SCREEN:
       if (!InputMethodUtil::IsKeyboardLayout(current_input_method)) {
         DVLOG(1) << "Only keyboard layouts are supported: "
                  << current_input_method;
         return;
       }
       PersistSystemInputMethod(current_input_method);
       return;
     case InputMethodManager::STATE_BROWSER_SCREEN:
-      PersistUserInputMethod(current_input_method);
+      PersistUserInputMethod(current_input_method, manager);
       return;
     case InputMethodManager::STATE_LOCK_SCREEN:
       // We use a special set of input methods on the screen. Do not update.
       return;
     case InputMethodManager::STATE_TERMINATING:
       return;
   }
   NOTREACHED();
 }
 
 void InputMethodPersistence::InputMethodPropertyChanged(
     InputMethodManager* manager) {}
 
 void InputMethodPersistence::OnSessionStateChange(
     InputMethodManager::State new_state) {
   state_ = new_state;
 }
 
 }  // namespace input_method
 }  // namespace chromeos