Fix trivial type-check errors in file_manager.

ui/file_manager/file_manager/foreground/js/ui/scrollbar.js

Index: ui/file_manager/file_manager/foreground/js/ui/scrollbar.js
diff --git a/ui/file_manager/file_manager/foreground/js/ui/scrollbar.js b/ui/file_manager/file_manager/foreground/js/ui/scrollbar.js
index 5a8e42caafe39398357fbe17360815933a68d307..3ba87b0b6f892c99f95a331e29b51576022bf1d1 100644
--- a/ui/file_manager/file_manager/foreground/js/ui/scrollbar.js
+++ b/ui/file_manager/file_manager/foreground/js/ui/scrollbar.js
@@ -13,7 +13,7 @@ var ScrollBar = cr.ui.define('div');
 
 /**
  * Mode of the scrollbar. As for now, only vertical scrollbars are supported.
- * @type {number}
+ * @enum {number}
  */
 ScrollBar.Mode = {
   VERTICAL: 0,
@@ -60,7 +60,7 @@ ScrollBar.prototype.decorate = function() {
 /**
  * Initialize a scrollbar.
  *
- * @param {Element} parent Parent element, must have a relative or absolute
+ * @param {Element} parent Parent node, must have a relative or absolute

[hirono, 2014/10/16 07:24:47]

nit: Parent node -> Parent element

[fukino, 2014/10/16 07:43:43]

Done.

  *     positioning.
  * @param {Element=} opt_scrollableArea Element with scrollable contents.
  *     If not passed, then call attachToView manually when the scrollable
@@ -81,7 +81,9 @@ ScrollBar.prototype.attachToView = function(view) {
   this.view_.addEventListener('scroll', this.onScroll_.bind(this));
   this.view_.addEventListener('relayout', this.onRelayout_.bind(this));
   this.domObserver_ = new MutationObserver(this.onDomChanged_.bind(this));
-  this.domObserver_.observe(this.view_, {subtree: true, attributes: true});
+  this.domObserver_.observe(
+      this.view_,
+      /** @type {MutationObserverInit} */ ({subtree: true, attributes: true}));
   this.onRelayout_();
 };