Add UMA stats for new Print Preview UI elements.

chrome/browser/resources/print_preview/settings/more_settings.js

 // Copyright 2014 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.
 
 cr.define('print_preview', function() {
   'use strict';
 
   /**
    * Toggles visibility of the specified printing options sections.
    * @param {!print_preview.DestinationStore} destinationStore To listen for
@@ skipping 13 matching lines @@
     this.settingsSections_ = settingsSections;
 
     /** @private {MoreSettings.SettingsToShow} */
     this.settingsToShow_ = MoreSettings.SettingsToShow.MOST_POPULAR;
 
     /** @private {boolean} */
     this.capabilitiesReady_ = false;
 
     /** @private {boolean} */
     this.firstDestinationReady_ = false;
+
+    /**
+     * Used to record usage statistics.
+     * @private {!print_preview.PrintSettingsUiMetricsContext}
+     */
+    this.metrics_ = new print_preview.PrintSettingsUiMetricsContext();
   };
 
   /**
    * Which settings are visible to the user.
    * @enum {number}
    */
   MoreSettings.SettingsToShow = {
     MOST_POPULAR: 1,
     ALL: 2
   };
 
   MoreSettings.prototype = {
     __proto__: print_preview.Component.prototype,
 
+    /** @return {boolean} Returns {@code true} if settings are expanded. */
+    get isExpanded() {
+      return this.settingsToShow_ == MoreSettings.SettingsToShow.ALL;
+    },
+
     /** @override */
     enterDocument: function() {
       print_preview.Component.prototype.enterDocument.call(this);
 
       this.tracker.add(this.getElement(), 'click', this.onClick_.bind(this));
       this.tracker.add(
           this.destinationStore_,
           print_preview.DestinationStore.EventType.DESTINATION_SELECT,
           this.onDestinationChanged_.bind(this));
       this.tracker.add(
@@ skipping 15 matching lines @@
      * Toggles "more/fewer options" state and notifies all the options sections
      *     to reflect the new state.
      * @private
      */
     onClick_: function() {
       this.settingsToShow_ =
           this.settingsToShow_ == MoreSettings.SettingsToShow.MOST_POPULAR ?
               MoreSettings.SettingsToShow.ALL :
               MoreSettings.SettingsToShow.MOST_POPULAR;
       this.updateState_(false);
+      this.metrics_.record(this.isExpanded ?
+          print_preview.Metrics.PrintSettingsUiBucket.MORE_SETTINGS_CLICKED :
+          print_preview.Metrics.PrintSettingsUiBucket.LESS_SETTINGS_CLICKED);
     },
 
     /**
      * Called when the destination selection has changed. Updates UI elements.
      * @private
      */
     onDestinationChanged_: function() {
       this.firstDestinationReady_ = true;
       this.capabilitiesReady_ = false;
       this.updateState_(false);
@@ skipping 56 matching lines @@
         section.setCollapseContent(collapseContent, noAnimation);
       });
     }
   };
 
   // Export
   return {
     MoreSettings: MoreSettings
   };
 });