Gallery: Update metadata in GalleryItem when saving items.

ui/file_manager/gallery/js/gallery_item_unittest.js

Index: ui/file_manager/gallery/js/gallery_item_unittest.js
diff --git a/ui/file_manager/gallery/js/gallery_item_unittest.js b/ui/file_manager/gallery/js/gallery_item_unittest.js
new file mode 100644
index 0000000000000000000000000000000000000000..e3c545b28593bb85fecba06b6eb8620a5e1956fc
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+++ b/ui/file_manager/gallery/js/gallery_item_unittest.js
@@ -0,0 +1,79 @@
+// 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.
+
+/**
+ * Mock of ImageUtil.
+ */
+var ImageUtil = {
+  getMetricName: function() {},
+  metrics: {
+    recordEnum: function() {},
+    recordInterval: function() {},
+    startInterval: function() {}
+  }
+};
+
+/**
+ * Mock of ImageEncoder
+ */
+var ImageEncoder = {
+  encodeMetadata: function() {},
+  getBlob: function() {}
+};
+
+/**
+ * Load time data.
+ */
+loadTimeData.data = {
+  DRIVE_DIRECTORY_LABEL: '',
+  DOWNLOADS_DIRECTORY_LABEL: ''
+};
+
+/**
+ * Tests for GalleryItem#saveToFile.
+ */
+function testSaveToFile(callback) {
+  var fileSystem = new MockFileSystem('volumeId');
+  fileSystem.populate(['/test.jpg']);
+  var entry = fileSystem.entries['/test.jpg'];
+  entry.createWriter = function(callback) {
+    callback({
+      write: function() {
+        Promise.resolve().then(function() {
+          this.onwriteend();
+        }.bind(this));
+      },
+      truncate: function() {
+        this.write();
+      }
+    });
+  };
+  var fetchedMediaCleared = false;
+  var metadataCache = {
+    getLatest: function(entries, type, callback) {
+      callback([{name: 'newMetadata'}]);
+    },
+    clear: function(entries, type) {
+      fetchedMediaCleared = true;
+    }
+  };
+  var item = new Gallery.Item(
+      entry,
+      {isReadOnly: false},
+      {name: 'oldMetadata'},
+      metadataCache,
+      /* original */ true);
+  assertEquals('oldMetadata', item.getMetadata().name);
+  assertFalse(fetchedMediaCleared);
+  reportPromise(
+      new Promise(item.saveToFile.bind(
+          item,
+          {getLocationInfo: function() { return {}; }},
+          null,
+          true,
+          document.createElement('canvas'))).then(function() {
+            assertEquals('newMetadata', item.getMetadata().name);
+            assertTrue(fetchedMediaCleared);
+          }), callback);
+}