Media Galleries: Add a dropPermissionForMediaFileSystem() 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 GetMediaFileSystemsInteractivity {
     // Do not act interactively.
@@ skipping 39 matching lines @@
     GetMetadataType? metadataType;
   };
 
   callback MediaFileSystemsCallback =
       void ([instanceOf=DOMFileSystem] object[] mediaFileSystems);
 
   callback AddUserFolderCallback =
       void ([instanceOf=DOMFileSystem] object[] mediaFileSystems,
             DOMString selectedFileSystemName);
 
+  callback ForgetMediaFileSystemCallback = void (boolean wasForgotten);

[vandebo (ex-Chrome), 2014/04/07 16:01:01]

Is there a usecase for this?  If we can't think of one, lets leave it out until
we find one.  It'd be easy to add in later.

[Lei Zhang, 2014/04/07 22:32:04]

Success is not guaranteed, so there should be someway of letting the caller know
in case of a failure. The alarms API is similar.
https://developer.chrome.com/apps/alarms#method-clearAll

[Lei Zhang, 2014/04/08 02:05:11]

Also, since the API is asynchronous, the caller can't count on the call to have
completed until the callback has occurred.

+
   [inline_doc] dictionary MediaFileSystemMetadata {
     // The name of the file system.
     DOMString name;
 
     // A unique and persistent id for the media gallery.
     DOMString galleryId;
 
     // If the media gallery is on a removable device, a unique id for the
     // device while the device is online.
     DOMString? deviceId;
@@ skipping 64 matching lines @@
     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
     // gesture, the callback will run as though the user canceled.
     static void addUserSelectedFolder(AddUserFolderCallback callback);
 
+    // Give up access to a given media gallery.
+    static void forgetMediaFileSystem(

[vandebo (ex-Chrome), 2014/04/07 16:01:01]

I think 'cede' or 'drop' would be better than 'forget'

+        [instanceOf=DOMFileSystem] object mediaFileSystem,

[vandebo (ex-Chrome), 2014/04/07 16:01:01]

Should this take a FS object, or a gallery id?  You need a FS object to get to a
gallery id, but apps can persist the gallery id's that they have access to and
thus use them as keys for FS's in there UI.  i.e. if there's a long unused
removable device, the app may have the gallery id, but can't get the FS
object...

[Lei Zhang, 2014/04/07 22:32:04]

Done.

+        optional ForgetMediaFileSystemCallback callback);
+
     // Start a scan of the user's hard disks for directories containing media.
     // The scan may take a long time so progress and completion is communicated
     // by events. No permission is granted as a result of the scan, see
     // addScanResults.
     static void startMediaScan();
 
     // Cancel any pending media scan.  Well behaved apps should provide a way
     // for the user to cancel scans they start.
     static void cancelMediaScan();
 
@@ skipping 17 matching lines @@
                             optional MediaMetadataOptions options,
                             MediaMetadataCallback callback);
   };
 
   interface Events {
     // The pending media scan has changed state. See details for more
     // information.
     static void onScanProgress(ScanProgressDetails details);
   };
 };