Storage manager: Hide "Offline files" when Google Drive volume is not mounted.

chrome/browser/resources/options/chromeos/storage_manager.js

Index: chrome/browser/resources/options/chromeos/storage_manager.js
diff --git a/chrome/browser/resources/options/chromeos/storage_manager.js b/chrome/browser/resources/options/chromeos/storage_manager.js
index 7ac72884b3f15d05c72bb2acfcd2643bef53e43c..eff5d0b1f5b294c92bd5b18ccbdff2e950e5a03f 100644
--- a/chrome/browser/resources/options/chromeos/storage_manager.js
+++ b/chrome/browser/resources/options/chromeos/storage_manager.js
@@ -131,6 +131,7 @@ cr.define('options', function() {
      * @private
      */
     setDriveCacheSize_: function(size) {
+      assert(!$('storage-manager-item-drive-cache').hidden);
       $('storage-manager-size-drive-cache').textContent = size;
     },
 
@@ -164,6 +165,14 @@ cr.define('options', function() {
     },
 
     /**
+     * Shows the item "Offline files" on the overlay UI.
+     * @private
+     */
+    showDriveCacheItem_: function() {
+      $('storage-manager-item-drive-cache').hidden = false;
+    },
+
+    /**
      * Shows the item "Android apps and cache" on the overlay UI.
      * @private
      */
@@ -205,6 +214,7 @@ cr.define('options', function() {
     'setOtherUsersSize',
     'setSizeStat',
     'showArcItem',
+    'showDriveCacheItem',
   ]);
 
   return {