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 edbed4055410f4b5c9027f3023dea245aa2fd68d..5662da4e9a5eb92deeb3733eab16e535dbfabb71 100644
--- a/chrome/browser/spellchecker/spellcheck_factory.cc
+++ b/chrome/browser/spellchecker/spellcheck_factory.cc
@@ -8,6 +8,7 @@
 #include "chrome/browser/profiles/incognito_helpers.h"
 #include "chrome/browser/spellchecker/spellcheck_service.h"
 #include "chrome/common/pref_names.h"
+#include "chrome/common/spellcheck_common.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"
@@ -69,9 +70,19 @@ KeyedService* SpellcheckServiceFactory::BuildServiceInstanceFor(
 void SpellcheckServiceFactory::RegisterProfilePrefs(
     user_prefs::PrefRegistrySyncable* user_prefs) {
   // TODO(estade): IDS_SPELLCHECK_DICTIONARY should be an ASCII string.
+
+  if (chrome::spellcheck_common::IsMultilingualSpellcheckEnabled()) {
+    user_prefs->RegisterStringPref(
+        prefs::kSpellCheckDictionaries,
+        l10n_util::GetStringUTF8(IDS_SPELLCHECK_DICTIONARY),
+        user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);

[please use gerrit instead, 2015/06/17 17:47:15]

prefs::kSpellCheckDictionary was not syncable originally. Let's not make
prefs::kSpellCheckDictionaries syncable.

[Julius, 2015/06/17 20:14:45]

Done.

+  }
+
   user_prefs->RegisterStringPref(
       prefs::kSpellCheckDictionary,
-      l10n_util::GetStringUTF8(IDS_SPELLCHECK_DICTIONARY));
+      l10n_util::GetStringUTF8(IDS_SPELLCHECK_DICTIONARY),
+      user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);

[please use gerrit instead, 2015/06/17 17:47:15]

This was not syncable before. Let's not make it syncable.

[Julius, 2015/06/17 20:14:45]

Done.

+
   user_prefs->RegisterBooleanPref(prefs::kSpellCheckUseSpellingService, false);
   user_prefs->RegisterBooleanPref(
       prefs::kEnableContinuousSpellcheck,