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

chrome/browser/ui/webui/options/language_options_handler_common.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/ui/webui/options/language_options_handler_common.h"
 
 #include <map>
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 114 matching lines @@
                          GetSpellCheckLanguageCodeSet());
   localized_strings->Set("uiLanguageCodeSet", GetUILanguageCodeSet());
 
   const base::CommandLine& command_line =
       *base::CommandLine::ForCurrentProcess();
   bool enable_spelling_auto_correct =
       command_line.HasSwitch(switches::kEnableSpellingAutoCorrect);
   localized_strings->SetBoolean("enableSpellingAutoCorrect",
                                 enable_spelling_auto_correct);
 
+  localized_strings->SetBoolean(
+      "enableMultilingualSpellChecker",
+      chrome::spellcheck_common::IsMultilingualSpellcheckEnabled());
+
   Profile* profile = Profile::FromWebUI(web_ui());
   PrefService* prefs = profile->GetPrefs();
   std::string default_target_language =
       TranslateService::GetTargetLanguage(prefs);
   localized_strings->SetString("defaultTargetLanguage",
                                default_target_language);
   localized_strings->SetBoolean(
       "enableMultilingualSpellChecker",
       chrome::spellcheck_common::IsMultilingualSpellcheckEnabled());
 
@@ skipping 102 matching lines @@
   SetApplicationLocale(language_code);
   base::StringValue language_value(language_code);
   web_ui()->CallJavascriptFunction("options.LanguageOptions.uiLanguageSaved",
                                    language_value);
 }
 
 void LanguageOptionsHandlerCommon::SpellCheckLanguageChangeCallback(
     const base::ListValue* args) {
   const std::string language_code =
       base::UTF16ToASCII(ExtractStringValue(args));
-  CHECK(!language_code.empty());

[Dan Beam, 2015/07/08 18:56:27]

why are you removing this?

[Julius, 2015/07/08 20:38:48]

language_code can actually be empty now because in multilingual spellchecking
the user can deselect all languages.

[Dan Beam, 2015/07/08 22:50:24]

why can they de-select all languages?

   const std::string action = base::StringPrintf(
       "LanguageOptions_SpellCheckLanguageChange_%s", language_code.c_str());
   content::RecordComputedAction(action);
   RefreshHunspellDictionary();
 }
 
 void LanguageOptionsHandlerCommon::UpdateLanguageListCallback(
     const base::ListValue* args) {
   CHECK_EQ(args->GetSize(), 1u);
   const base::ListValue* language_list;
@@ skipping 31 matching lines @@
 }
 
 base::WeakPtr<SpellcheckHunspellDictionary>&
     LanguageOptionsHandlerCommon::GetHunspellDictionary() {
   if (!hunspell_dictionary_.get())
     RefreshHunspellDictionary();
   return hunspell_dictionary_;
 }
 
 }  // namespace options