Gallery: Fix the slide show mode.

ui/file_manager/gallery/js/image_editor/image_view.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.
 
 'use strict';
 
 /**
  * The overlay displaying the image.
  *
  * @param {HTMLElement} container The container element.
@@ skipping 111 matching lines @@
     this.paintDeviceRect(this.contentCanvas_, new Rect(this.contentCanvas_));
     ImageUtil.trace.reportTimer('paint');
   }
 };
 
 /**
  * Applies the viewport change that does not affect the screen cache size (zoom
  * change or offset change) with animation.
  */
 ImageView.prototype.applyViewportChange = function() {
-  this.setTransform(
-      this.screenImage_,
-      new ImageView.Effect.None(),
-      ImageView.Effect.DEFAULT_DURATION);
+  if (this.screenImage_) {
+    this.setTransform(
+        this.screenImage_,
+        new ImageView.Effect.None(),
+        ImageView.Effect.DEFAULT_DURATION);
+  }
 };
 
 /**
  * @return {number} The cache generation.
  */
 ImageView.prototype.getCacheGeneration = function() {
   return this.contentGeneration_;
 };
 
 /**
@@ skipping 822 matching lines @@
 };
 
 ImageView.Effect.Rotate.prototype = { __proto__: ImageView.Effect.prototype };
 
 /**
  * @override
  */
 ImageView.Effect.Rotate.prototype.transform = function(element, viewport) {
   return viewport.getInverseTransformForRotatedImage(this.orientation_);
 };