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

chrome/browser/spellchecker/spellcheck_factory.cc

Index: chrome/browser/spellchecker/spellcheck_factory.cc
diff --git a/chrome/browser/spellchecker/spellcheck_factory.cc b/chrome/browser/spellchecker/spellcheck_factory.cc
index 8df78f46373675ed8429088611998a4039881e01..8720f22f59d6ed0c5ced85f9eee7889f1f2ff4cb 100644
--- a/chrome/browser/spellchecker/spellcheck_factory.cc
+++ b/chrome/browser/spellchecker/spellcheck_factory.cc
@@ -4,9 +4,11 @@
 
 #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"
@@ -67,10 +69,20 @@ KeyedService* SpellcheckServiceFactory::BuildServiceInstanceFor(
 void SpellcheckServiceFactory::RegisterProfilePrefs(
     user_prefs::PrefRegistrySyncable* user_prefs) {
   // TODO(estade): IDS_SPELLCHECK_DICTIONARY should be an ASCII string.
+
+  const CommandLine* command_line = CommandLine::ForCurrentProcess();
+  if (command_line->HasSwitch(switches::kEnableMultilingualSpellChecker)) {
+    user_prefs->RegisterLocalizedStringPref(
+        prefs::kSpellCheckDictionaries,
+        IDS_SPELLCHECK_DICTIONARY,
+        user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
+  }
+
   user_prefs->RegisterLocalizedStringPref(
       prefs::kSpellCheckDictionary,
       IDS_SPELLCHECK_DICTIONARY,
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
+
   user_prefs->RegisterBooleanPref(
       prefs::kSpellCheckUseSpellingService,
       false,