Enables the user to select multiple languages for spellchecking (UI)

chrome/browser/spellchecker/spellcheck_factory.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/spellchecker/spellcheck_factory.h"
 
+#include "base/command_line.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/profiles/incognito_helpers.h"
 #include "chrome/browser/spellchecker/spellcheck_service.h"
+#include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/grit/locale_settings.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 #include "components/user_prefs/user_prefs.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/render_process_host.h"
 #include "ui/base/l10n/l10n_util.h"
 
 // static
@@ skipping 42 matching lines @@
   // Instantiates Metrics object for spellchecking for use.
   spellcheck->StartRecordingMetrics(
       prefs->GetBoolean(prefs::kEnableContinuousSpellcheck));
 
   return spellcheck;
 }
 
 void SpellcheckServiceFactory::RegisterProfilePrefs(
     user_prefs::PrefRegistrySyncable* user_prefs) {
   // TODO(estade): IDS_SPELLCHECK_DICTIONARY should be an ASCII string.
-  user_prefs->RegisterStringPref(
-      prefs::kSpellCheckDictionary,
-      l10n_util::GetStringUTF8(IDS_SPELLCHECK_DICTIONARY));
+
+  // TODO(juliusa): Implement preference migration between multilingual
+  // spellchecking and single-language spellchecking.
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kEnableMultilingualSpellChecker)) {
+    user_prefs->RegisterStringPref(
+        prefs::kSpellCheckDictionaries,
+        l10n_util::GetStringUTF8(IDS_SPELLCHECK_DICTIONARY),
+        user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
+  } else {
+    user_prefs->RegisterStringPref(
+        prefs::kSpellCheckDictionary,
+        l10n_util::GetStringUTF8(IDS_SPELLCHECK_DICTIONARY),
+        user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
+  }
+
   user_prefs->RegisterBooleanPref(prefs::kSpellCheckUseSpellingService, false);
   user_prefs->RegisterBooleanPref(
       prefs::kEnableContinuousSpellcheck,
       true,
       user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
   user_prefs->RegisterBooleanPref(
       prefs::kEnableAutoSpellCorrect,
       false,
       user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
 }
 
 content::BrowserContext* SpellcheckServiceFactory::GetBrowserContextToUse(
     content::BrowserContext* context) const {
   return chrome::GetBrowserContextRedirectedInIncognito(context);
 }
 
 bool SpellcheckServiceFactory::ServiceIsNULLWhileTesting() const {
   return true;
 }