Expose gallery watching functionality to the public mediaGalleries API.

chrome/common/extensions/api/media_galleries.idl

 // Copyright (c) 2012 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 the <code>chrome.mediaGalleries</code> API to access media files (audio,
 // images, video) from the user's local disks (with the user's consent).
 namespace mediaGalleries {
 
   [inline_doc] enum GalleryChangeType {
     // The contents of the gallery have changed.
@@ skipping 155 matching lines @@
     // stream order will be preserved. Container metadata is the first element.
     StreamInfo[] rawTags;
 
     // The images embedded in the media file's metadata. This is most often
     // used for album art or video thumbnails.
     [instanceOf=Blob] object[] attachedImages;
   };
 
   callback MediaMetadataCallback = void (MediaMetadata metadata);
 
+  // A dictionary that describes the add gallery watch request results.
+  dictionary AddGalleryWatchResult {
+    DOMString galleryId;
+    boolean success;
+  };
+
+  callback AddGalleryWatchCallback = void (AddGalleryWatchResult result);
+  callback GetAllGalleryWatchCallback = void (DOMString[] galleryIds);
+
   interface Functions {
     // Get the media galleries configured in this user agent. If none are
     // configured or available, the callback will receive an empty array.
     static void getMediaFileSystems(optional MediaFileSystemsDetails details,
                                     MediaFileSystemsCallback callback);
 
     // Present a directory picker to the user and add the selected directory
     // as a gallery. If the user cancels the picker, selectedFileSystemName
     // will be empty.
     // A user gesture is required for the dialog to display. Without a user
@@ skipping 27 matching lines @@
 
     // Get metadata for all available media galleries.
     static void getAllMediaFileSystemMetadata(
         MediaFileSystemsMetadataCallback callback);
 
     // Gets the media-specific metadata for a media file. This should work
     // for files in media galleries as well as other DOM filesystems.
     static void getMetadata([instanceOf=Blob] object mediaFile,
                             optional MediaMetadataOptions options,
                             MediaMetadataCallback callback);
+
+    // Adds a gallery watch for the gallery with the specified gallery ID.
+    // The given callback is then fired with a success or failure result.
+    static void addGalleryWatch(DOMString galleryId,
+                                AddGalleryWatchCallback callback);
+
+    // Removes a gallery watch for the gallery with the specified gallery ID.
+    static void removeGalleryWatch(DOMString galleryId);
+
+    // Notifies which galleries are being watched via the given callback.
+    static void getAllGalleryWatch(GetAllGalleryWatchCallback callback);
+
+    // Removes all gallery watches.
+    static void removeAllGalleryWatch();
   };
 
   interface Events {
     // Fired when a media gallery is changed or a gallery watch is dropped.
     static void onGalleryChanged(GalleryChangeDetails details);
 
     // The pending media scan has changed state. See details for more
     // information.
     static void onScanProgress(ScanProgressDetails details);
   };
 };