MD Settings: Restore focus after exiting various subpages.

chrome/browser/resources/settings/languages_page/languages_page.js

 // Copyright 2015 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.
 
 /**
  * @fileoverview 'settings-languages-page' is the settings page
  * for language and input method settings.
  */
 cr.exportPath('settings');
 
@@ skipping 40 matching lines @@
 
     /**
      * The language to display the details for.
      * @type {!LanguageState|undefined}
      * @private
      */
     detailLanguage_: Object,
 
     /** @private */
     showAddLanguagesDialog_: Boolean,
+
+    /** @private {?Map<string, string>} */
+    focusConfig_: Object,
+  },
+
+  /** @override */
+  ready: function() {
+    this.focusConfig_ = new Map();
+// <if expr="not is_macosx">

[Dan Beam, 2017/04/11 02:23:56]

fwiw: these will eventually get reformatted with `git cl format --js` to be
indented with the code

+    this.focusConfig_.set(
+        settings.Route.EDIT_DICTIONARY.path,
+        '#spellCheckCollapse .subpage-arrow');
+// </if>
+// <if expr="chromeos">
+    this.focusConfig_.set(
+        settings.Route.INPUT_METHODS.path,
+        '#inputMethodsCollapse .subpage-arrow');
+// </if>
   },
 
   /**
    * Handler for enabling or disabling spell check.
    * @param {!{target: Element, model: !{item: !LanguageState}}} e
    */
   onSpellCheckChange_: function(e) {
     var item = e.model.item;
     if (!item.language.supportsSpellcheck)
       return;
@@ skipping 467 matching lines @@
     if (e.target.tagName == expandButtonTag)
       return;
 
     /** @type {!CrExpandButtonElement} */
     var expandButton = e.currentTarget.querySelector(expandButtonTag);
     assert(expandButton);
     expandButton.expanded = !expandButton.expanded;
   },
 });
 })();