Gallery: Start to use new metadata model in Gallery.

ui/file_manager/gallery/js/gallery_data_model.js

 // Copyright 2015 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.
 
 /**
  * Data model for gallery.
  *
  * @param {!MetadataCache} metadataCache Metadata cache.
  * @param {!MetadataModel} metadataModel
  * @param {!EntryListWatcher=} opt_watcher Entry list watcher.
@@ skipping 55 matching lines @@
  * @param {!VolumeManager} volumeManager Volume manager instance.
  * @param {!Gallery.Item} item Original gallery item.
  * @param {!HTMLCanvasElement} canvas Canvas containing new image.
  * @param {boolean} overwrite Whether to overwrite the image to the item or not.
  * @return {!Promise} Promise to be fulfilled with when the operation completes.
  */
 GalleryDataModel.prototype.saveItem = function(
     volumeManager, item, canvas, overwrite) {
   var oldEntry = item.getEntry();
   var oldMetadata = item.getMetadata();
+  var oldMetadataItem = item.getMetadataItem();
   var oldLocationInfo = item.getLocationInfo();
   return new Promise(function(fulfill, reject) {
     item.saveToFile(
         volumeManager,
         this.fallbackSaveDirectory,
         overwrite,
         canvas,
         function(success) {
           if (!success) {
             reject('Failed to save the image.');
             return;
           }
 
           // Current entry is updated.
           // Dispatch an event.
           var event = new Event('content');
           event.item = item;
           event.oldEntry = oldEntry;
           event.metadata = item.getMetadata();
           this.dispatchEvent(event);
 
           if (!util.isSameEntry(oldEntry, item.getEntry())) {
             // New entry is added and the item now tracks it.
             // Add another item for the old entry.
             var anotherItem = new Gallery.Item(
                 oldEntry,
                 oldLocationInfo,
                 oldMetadata,
+                oldMetadataItem,
                 this.metadataCache_,
                 this.metadataModel_,
                 item.isOriginal());
             // The item must be added behind the existing item so that it does
             // not change the index of the existing item.
             // TODO(hirono): Update the item index of the selection model
             // correctly.
             this.splice(this.indexOf(item) + 1, 0, anotherItem);
           }
 
@@ skipping 34 matching lines @@
         } else {
           // Force to free the buffer of the canvas by assigning zero size.
           sorted[i].screenImage.width = 0;
           sorted[i].screenImage.height = 0;
           sorted[i].screenImage = null;
         }
       }
     }
   }
 };