Gallery: Start to use new metadata model in Gallery.

ui/file_manager/gallery/js/gallery_item.js

Index: ui/file_manager/gallery/js/gallery_item.js
diff --git a/ui/file_manager/gallery/js/gallery_item.js b/ui/file_manager/gallery/js/gallery_item.js
index 6d87f3ea692973a0fe5d86e704513e2a04707b0c..65641ebf176c9119b9a4f8de7067b60a551f2daa 100644
--- a/ui/file_manager/gallery/js/gallery_item.js
+++ b/ui/file_manager/gallery/js/gallery_item.js
@@ -8,6 +8,7 @@
  * @param {!FileEntry} entry Image entry.
  * @param {!EntryLocation} locationInfo Entry location information.
  * @param {!Object} metadata Metadata for the entry.
+ * @param {!MetadataItem} metadataItem
  * @param {!MetadataCache} metadataCache Metadata cache instance.
  * @param {!MetadataModel} metadataModel File system metadata.
  * @param {boolean} original Whether the entry is original or edited.
@@ -15,8 +16,8 @@
  * @struct
  */
 Gallery.Item = function(
-    entry, locationInfo, metadata, metadataCache, metadataModel,
-    original) {
+    entry, locationInfo, metadata, metadataItem, metadataCache,
+    metadataModel, original) {
   /**
    * @type {!FileEntry}
    * @private
@@ -36,6 +37,11 @@ Gallery.Item = function(
   this.metadata_ = Object.preventExtensions(metadata);
 
   /**
+   * @type {!MetadataItem}
+   */
+  this.metadataItem_ = metadataItem;
+
+  /**
    * @type {!MetadataCache}
    * @private
    * @const
@@ -100,24 +106,10 @@ Gallery.Item.prototype.getLocationInfo = function() {
 Gallery.Item.prototype.getMetadata = function() { return this.metadata_; };
 
 /**
- * Obtains the latest media metadata.
- *
- * This is a heavy operation since it forces to load the image data to obtain
- * the metadata.
- * @return {!Promise} Promise to be fulfilled with fetched metadata.
+ * @return {!MetadataItem} Metadata.
  */
-Gallery.Item.prototype.getFetchedMedia = function() {
-  return new Promise(function(fulfill, reject) {
-    this.metadataCache_.getLatest(
-        [this.entry_],
-        'fetchedMedia',
-        function(metadata) {
-          if (metadata[0])
-            fulfill(metadata[0]);
-          else
-            reject('Failed to load metadata.');
-        });
-  }.bind(this));
+Gallery.Item.prototype.getMetadataItem = function() {
+  return this.metadataItem_;
 };
 
 /**