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

chrome/browser/resources/options/language_options.js

Index: chrome/browser/resources/options/language_options.js
diff --git a/chrome/browser/resources/options/language_options.js b/chrome/browser/resources/options/language_options.js
index 7956e85ab74770a6306bfd4e1f677eb8de494e52..01a240b7661d78bdeec70891e9e0c5f6e1b109f2 100644
--- a/chrome/browser/resources/options/language_options.js
+++ b/chrome/browser/resources/options/language_options.js
@@ -60,6 +60,14 @@ cr.define('options', function() {
   var SPELL_CHECK_DICTIONARY_PREF = 'spellcheck.dictionary';
 
   /**
+   * The preference key that describes the spell check dictionary languages
+   * currently selected (as a comma separated string, like "en-US,sl-SI").
+   * @type {string}
+   * @const
+   */
+  var SPELL_CHECK_DICTIONARIES_PREF = 'spellcheck.dictionaries';
+
+  /**
    * The preference that indicates if the Translate feature is enabled.
    * @type {string}
    * @const
@@ -144,6 +152,14 @@ cr.define('options', function() {
     spellCheckDictionary_: '',
 
     /**
+     * The dictionary of currently selected spell check dictionary languages,
+     * like "{"en-US": true, "sl-SI": true}".
+     * @type {Object}
+     * @private
+     */
+    spellCheckDictionaries_: {},
+
+    /**
      * The map of language code to input method IDs, like:
      * {'ja': ['mozc', 'mozc-jp'], 'zh-CN': ['pinyin'], ...}
      * @type {Object}
@@ -187,8 +203,16 @@ cr.define('options', function() {
       Preferences.getInstance().addEventListener(
           TRANSLATE_BLOCKED_LANGUAGES_PREF,
           this.handleTranslateBlockedLanguagesPrefChange_.bind(this));
-      Preferences.getInstance().addEventListener(SPELL_CHECK_DICTIONARY_PREF,
+
+      if (loadTimeData.getBoolean('enableMultilingualSpellChecker')) {
+        Preferences.getInstance().addEventListener(
+            SPELL_CHECK_DICTIONARIES_PREF,
+            this.handleSpellCheckDictionariesPrefChange_.bind(this));
+      } else {
+        Preferences.getInstance().addEventListener(SPELL_CHECK_DICTIONARY_PREF,
           this.handleSpellCheckDictionaryPrefChange_.bind(this));
+      }
+
       Preferences.getInstance().addEventListener(ENABLE_TRANSLATE,
           this.handleEnableTranslatePrefChange_.bind(this));
       this.translateSupportedLanguages_ =
@@ -240,11 +264,19 @@ cr.define('options', function() {
 
       // Handle clicks on "Use this language for spell checking" button.
       if (!cr.isMac) {
-        var spellCheckLanguageButton = getRequiredElement(
-            'language-options-spell-check-language-button');
-        spellCheckLanguageButton.addEventListener(
-            'click',
-            this.handleSpellCheckLanguageButtonClick_.bind(this));
+        if (loadTimeData.getBoolean('enableMultilingualSpellChecker')) {
+          var spellCheckLanguageCheckbox = getRequiredElement(
+              'language-options-spell-check-language-checkbox');
+          spellCheckLanguageCheckbox.addEventListener(
+              'click',
+              this.handleSpellCheckLanguageCheckboxClick_.bind(this));
+        } else {
+          var spellCheckLanguageButton = getRequiredElement(
+              'language-options-spell-check-language-button');
+          spellCheckLanguageButton.addEventListener(
+              'click',
+              this.handleSpellCheckLanguageButtonClick_.bind(this));
+        }
       }
 
       if (cr.isChromeOS) {
@@ -427,7 +459,7 @@ cr.define('options', function() {
       this.updateSelectedLanguageName_(languageCode);
 
       if (!cr.isMac)
-        this.updateSpellCheckLanguageButton_(languageCode);
+        this.updateSpellCheckLanguageControls_(languageCode);
 
       if (cr.isChromeOS)
         this.updateInputMethodList_(languageCode);
@@ -604,10 +636,14 @@ cr.define('options', function() {
      * @param {string} languageCode Language code (ex. "fr").
      * @private
      */
-    updateSpellCheckLanguageButton_: function(languageCode) {
+    updateSpellCheckLanguageControls_: function(languageCode) {
       var spellCheckLanguageSection = $('language-options-spellcheck');
       var spellCheckLanguageButton =
           $('language-options-spell-check-language-button');
+      var spellCheckLanguageCheckboxDiv =
+          $('language-options-spell-check-language-checkbox-div');
+      var spellCheckLanguageCheckbox =
+          $('language-options-spell-check-language-checkbox');
       var spellCheckLanguageMessage =
           $('language-options-spell-check-language-message');
       var dictionaryDownloadInProgress =
@@ -616,44 +652,53 @@ cr.define('options', function() {
           $('language-options-dictionary-download-failed-message');
       var dictionaryDownloadFailHelp =
           $('language-options-dictionary-download-fail-help-message');
+
       spellCheckLanguageSection.hidden = false;
       spellCheckLanguageMessage.hidden = true;
       spellCheckLanguageButton.hidden = true;
+      spellCheckLanguageCheckboxDiv.hidden = true;
       dictionaryDownloadInProgress.hidden = true;
       dictionaryDownloadFailed.hidden = true;
       dictionaryDownloadFailHelp.hidden = true;
 
-      if (languageCode == this.spellCheckDictionary_) {
-        if (!(languageCode in this.spellcheckDictionaryDownloadStatus_)) {
-          spellCheckLanguageMessage.textContent =
-              loadTimeData.getString('isUsedForSpellChecking');
-          showMutuallyExclusiveNodes(
-              [spellCheckLanguageButton, spellCheckLanguageMessage], 1);
-        } else if (this.spellcheckDictionaryDownloadStatus_[languageCode] ==
-                       DOWNLOAD_STATUS.IN_PROGRESS) {
+      spellCheckLanguageCheckbox.checked = false;
+
+      if (!languageCode)
+        return;
+
+      if (languageCode in loadTimeData.getValue('spellCheckLanguageCodeSet')) {
+        if (loadTimeData.getBoolean('enableMultilingualSpellChecker')) {
+          spellCheckLanguageCheckbox.languageCode = languageCode;
+          if (this.spellCheckDictionaries_.hasOwnProperty(languageCode))
+            spellCheckLanguageCheckbox.checked = true;
+
+          spellCheckLanguageCheckboxDiv.hidden = false;
+        } else if (languageCode == this.spellCheckDictionary_) {
+          if (!(languageCode in this.spellcheckDictionaryDownloadStatus_)) {
+            spellCheckLanguageMessage.textContent =
+                loadTimeData.getString('isUsedForSpellChecking');
+            spellCheckLanguageMessage.hidden = false;
+          }
+        } else {
+          spellCheckLanguageButton.textContent =
+              loadTimeData.getString('useThisForSpellChecking');
+          spellCheckLanguageButton.hidden = false;
+        }
+
+        if (this.spellcheckDictionaryDownloadStatus_[languageCode] ==
+                DOWNLOAD_STATUS.IN_PROGRESS) {
           dictionaryDownloadInProgress.hidden = false;
         } else if (this.spellcheckDictionaryDownloadStatus_[languageCode] ==
                        DOWNLOAD_STATUS.FAILED) {
-          spellCheckLanguageSection.hidden = true;
-          dictionaryDownloadFailed.hidden = false;
+          showMutuallyExclusiveNodes(
+              [spellCheckLanguageSection, dictionaryDownloadFailed], 1);
           if (this.spellcheckDictionaryDownloadFailures_ > 1)
             dictionaryDownloadFailHelp.hidden = false;
         }
-      } else if (languageCode in
-          loadTimeData.getValue('spellCheckLanguageCodeSet')) {
-        spellCheckLanguageButton.textContent =
-            loadTimeData.getString('useThisForSpellChecking');
-        showMutuallyExclusiveNodes(
-            [spellCheckLanguageButton, spellCheckLanguageMessage], 0);
-        spellCheckLanguageButton.languageCode = languageCode;
-      } else if (!languageCode) {
-        spellCheckLanguageButton.hidden = true;
-        spellCheckLanguageMessage.hidden = true;
       } else {
         spellCheckLanguageMessage.textContent =
             loadTimeData.getString('cannotBeUsedForSpellChecking');
-        showMutuallyExclusiveNodes(
-            [spellCheckLanguageButton, spellCheckLanguageMessage], 1);
+        spellCheckLanguageMessage.hidden = false;
       }
     },
 
@@ -945,12 +990,34 @@ cr.define('options', function() {
       var languageCode = e.value.value;
       this.spellCheckDictionary_ = languageCode;
       if (!cr.isMac) {
-        this.updateSpellCheckLanguageButton_(
+        this.updateSpellCheckLanguageControls_(
             $('language-options-list').getSelectedLanguageCode());
       }
     },
 
     /**
+     * Updates spellcheck dictionary UI (checkboxes, buttons, and labels) when
+     * preferences change.
+     * @param {Event} e. Preference change event where e.value.value is the
+     * comma separated list of languages currently used for spellchecking.
+     * @private
+     */
+    handleSpellCheckDictionariesPrefChange_: function(e) {
+      if (cr.isMac)
+        return;
+
+      var commaSeparatedLanguageCodes = e.value.value;
+      var languageCodesSplit = commaSeparatedLanguageCodes.split(',');
+
+      this.spellCheckDictionaries_ = {};
+      for (var i = 0; i < languageCodesSplit.length; i++)
+        this.spellCheckDictionaries_[languageCodesSplit[i]] = true;
+
+      this.updateSpellCheckLanguageControls_(
+          $('language-options-list').getSelectedLanguageCode());
+    },
+
+    /**
      * Handles translate.enabled change.
      * @param {Event} e Change event.
      * @private
@@ -978,6 +1045,31 @@ cr.define('options', function() {
     },
 
     /**
+     * Updates the spellcheck.dictionaries preference with the currently
+     * selected language codes.
+     * @param {Event} e Click event. e.target represents the "Use this language
+     * for spellchecking"
+     * @private
+     */
+    handleSpellCheckLanguageCheckboxClick_: function(e) {
+      var languageCode = e.target.languageCode;
+
+      if (e.target.checked)
+        this.spellCheckDictionaries_[languageCode] = true;
+      else
+        delete this.spellCheckDictionaries_[languageCode];
+
+      var languageCodes = [];
+      for (var currentLanguageCode in this.spellCheckDictionaries_) {
+        if (this.spellCheckDictionaries_.hasOwnProperty(currentLanguageCode))
+          languageCodes.push(currentLanguageCode);
+      }
+
+      Preferences.setStringPref(SPELL_CHECK_DICTIONARIES_PREF,
+                                languageCodes.join(','), true);
+    },
+
+    /**
      * Checks whether it's possible to remove the language specified by
      * languageCode and returns true if possible. This function returns false
      * if the removal causes the number of preload engines to be zero.
@@ -1276,7 +1368,7 @@ cr.define('options', function() {
       if (!cr.isMac &&
           languageCode ==
               $('language-options-list').getSelectedLanguageCode()) {
-        this.updateSpellCheckLanguageButton_(languageCode);
+        this.updateSpellCheckLanguageControls_(languageCode);
       }
     },
 
@@ -1292,7 +1384,7 @@ cr.define('options', function() {
       if (!cr.isMac &&
           languageCode ==
               $('language-options-list').getSelectedLanguageCode()) {
-        this.updateSpellCheckLanguageButton_(languageCode);
+        this.updateSpellCheckLanguageControls_(languageCode);
       }
     },
 
@@ -1309,7 +1401,7 @@ cr.define('options', function() {
       if (!cr.isMac &&
           languageCode ==
               $('language-options-list').getSelectedLanguageCode()) {
-        this.updateSpellCheckLanguageButton_(languageCode);
+        this.updateSpellCheckLanguageControls_(languageCode);
       }
     },