IME refactoring: ChromeOS introduce input methods State.

chrome/browser/chromeos/preferences.cc

Index: chrome/browser/chromeos/preferences.cc
diff --git a/chrome/browser/chromeos/preferences.cc b/chrome/browser/chromeos/preferences.cc
index 1a792e0206025446cb4d1d8b25e29ea1fc4dbe42..648318f094261824d227cd0e5507074a3b511c11 100644
--- a/chrome/browser/chromeos/preferences.cc
+++ b/chrome/browser/chromeos/preferences.cc
@@ -51,7 +51,8 @@ Preferences::Preferences()
     : prefs_(NULL),
       input_method_manager_(input_method::InputMethodManager::Get()),
       user_(NULL),
-      user_is_primary_(false) {
+      user_is_primary_(false),
+      ime_state_outdated_(true) {
   // Do not observe shell, if there is no shell instance; e.g., in some unit
   // tests.
   if (ash::Shell::HasInstance())
@@ -62,7 +63,8 @@ Preferences::Preferences(input_method::InputMethodManager* input_method_manager)
     : prefs_(NULL),
       input_method_manager_(input_method_manager),
       user_(NULL),
-      user_is_primary_(false) {
+      user_is_primary_(false),
+      ime_state_outdated_(true) {
   // Do not observe shell, if there is no shell instance; e.g., in some unit
   // tests.
   if (ash::Shell::HasInstance())
@@ -537,12 +539,15 @@ void Preferences::ApplyPreferences(ApplyReason reason,
       UpdateAutoRepeatRate();
   }
 
-  if (reason != REASON_PREF_CHANGED && user_is_active) {
-    SetInputMethodList();
-  } else if (pref_name == prefs::kLanguagePreloadEngines && user_is_active) {
-    SetLanguageConfigStringListAsCSV(language_prefs::kGeneralSectionName,
-                                     language_prefs::kPreloadEnginesConfigName,
-                                     preload_engines_.GetValue());
+  if (pref_name == prefs::kLanguagePreloadEngines) {
+    if (reason == REASON_PREF_CHANGED && user_is_active) {
+      SetLanguageConfigStringListAsCSV(
+          language_prefs::kGeneralSectionName,
+          language_prefs::kPreloadEnginesConfigName,
+          preload_engines_.GetValue());
+    } else {
+      ime_state_outdated_ = true;
+    }
   }
 
   if (reason != REASON_PREF_CHANGED ||
@@ -646,9 +651,26 @@ void Preferences::OnTouchHudProjectionToggled(bool enabled) {
   touch_hud_projection_enabled_.SetValue(enabled);
 }
 
+void Preferences::ActivateInputMethods(const User* active_user) {
+  bool just_created = false;
+  if (!ime_state_) {

[Shu Chen, 2014/08/04 14:55:24]

I don't understand. Will there be single InputMethodManager::State shared for
multiple users?

[Alexander Alekseev, 2014/08/06 23:39:45]

No. Preferences belong to particular user, so this is lazy initialization of
per-user State object. 

+    ime_state_ = input_method::InputMethodManager::Get()->CreateNewState(
+        active_user->email());
+    just_created = true;
+  }
+  input_method::InputMethodManager::Get()->SetState(ime_state_);
+  if (just_created || ime_state_outdated_) {
+    SetInputMethodList();
+    ime_state_outdated_ = false;
+  }
+}
+
 void Preferences::ActiveUserChanged(const User* active_user) {
   if (active_user != user_)
     return;
+
+  ActivateInputMethods(active_user);
+
   ApplyPreferences(REASON_ACTIVE_USER_CHANGED, "");
 }