Add an option in language settings for activating the IME menu.

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 e0810c895c9b77202ef28380db81f9bfe7af942f..64b8fd475bb603532e56d610df0bae783c13dc83 100644
--- a/chrome/browser/chromeos/preferences.cc
+++ b/chrome/browser/chromeos/preferences.cc
@@ -285,6 +285,8 @@ void Preferences::RegisterProfilePrefs(
                                 true);
 
   registry->RegisterBooleanPref(prefs::kForceMaximizeOnFirstRun, false);
+
+  registry->RegisterBooleanPref(prefs::kLangugaeActivateImeMenu, false);

[Shu Chen, 2015/12/28 16:41:47]

pls put this behind a flag.

[Azure Wei, 2016/01/04 06:30:38]

Added a new flag 'enable-ime-menu'.

 }
 
 void Preferences::InitUserPrefs(syncable_prefs::PrefServiceSyncable* prefs) {
@@ -317,6 +319,7 @@ void Preferences::InitUserPrefs(syncable_prefs::PrefServiceSyncable* prefs) {
                              prefs, callback);
   previous_input_method_.Init(prefs::kLanguagePreviousInputMethod,
                               prefs, callback);
+  ime_menu_activated_.Init(prefs::kLangugaeActivateImeMenu, prefs, callback);
 
   xkb_auto_repeat_enabled_.Init(
       prefs::kLanguageXkbAutoRepeatEnabled, prefs, callback);
@@ -582,6 +585,16 @@ void Preferences::ApplyPreferences(ApplyReason reason,
     ime_state_->SetEnabledExtensionImes(&split_values);
   }
 
+  if (pref_name == prefs::kLangugaeActivateImeMenu &&
+      reason == REASON_PREF_CHANGED) {
+    const bool activated = ime_menu_activated_.GetValue();
+    if (activated) {
+      input_method_manager_->ImeMenuActivated();
+    } else {
+      input_method_manager_->ImeMenuDeactivated();
+    }
+  }
+
   if (user_is_active) {
     system::InputDeviceSettings::Get()->UpdateTouchpadSettings(
         touchpad_settings);