Add UMA stats for new Print Preview UI elements.

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

Index: chrome/browser/resources/print_preview/settings/more_settings.js
diff --git a/chrome/browser/resources/print_preview/settings/more_settings.js b/chrome/browser/resources/print_preview/settings/more_settings.js
index 7f924eeb2b0811aad675ec70c00176f51151a46d..8a3d5f6fd2f6f490a9a84c8b35b628a636f04870 100644
--- a/chrome/browser/resources/print_preview/settings/more_settings.js
+++ b/chrome/browser/resources/print_preview/settings/more_settings.js
@@ -31,6 +31,12 @@ cr.define('print_preview', function() {
 
     /** @private {boolean} */
     this.firstDestinationReady_ = false;
+
+    /**
+     * Used to record usage statistics.
+     * @private {!print_preview.PrintSettingsUiMetricsContext}
+     */
+    this.metrics_ = new print_preview.PrintSettingsUiMetricsContext();
   };
 
   /**
@@ -45,6 +51,11 @@ cr.define('print_preview', function() {
   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);
@@ -80,6 +91,9 @@ cr.define('print_preview', function() {
               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);
     },
 
     /**