Add mailbox-based Mojo VideoFrame variant.

media/mojo/interfaces/video_decoder.mojom

 // Copyright 2016 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.
 
 module media.mojom;
 
+import "gpu/ipc/common/sync_token.mojom";
 import "media/mojo/interfaces/media_types.mojom";
 import "mojo/common/unguessable_token.mojom";
 
 // Identifies a GpuCommandBufferStub. MediaGpuChannelManager is responsible
 // for minting |channel_token| objects.
 struct CommandBufferId {
   mojo.common.mojom.UnguessableToken channel_token;
   int32 route_id;
 };
 
@@ skipping 41 matching lines @@
   //
   // If |buffer| is an EOS buffer, implementations must execute all other
   // pending Decode() callbacks and output all pending frames before executing
   // the Decode(EOS) callback. (That is, they must flush.)
   Decode(DecoderBuffer buffer) => (DecodeStatus status);
 
   // Reset the decoder. All ongoing Decode() requests must be completed or
   // aborted before executing the callback. This must not be called while there
   // is a pending Initialize() request.
   Reset() => ();
+
+  // Inform the decoder that the client is finished with a frame.
+  // |release_sync_token| is a (possibly empty) sync point after which the
+  // frame's backing textures will be safe to overwrite.
+  OnReleaseMailbox(mojo.common.mojom.UnguessableToken release_token,
+                   gpu.mojom.SyncToken release_sync_token);
 };
 
 interface VideoDecoderClient {
-  // Output a decoded frame. Frames must be output in presentation order.
-  OnVideoFrameDecoded(VideoFrame frame);
+  // Output a decoded frame. Frames must be output in presentation order. If
+  // |release_token| is provided, the client should call OnReleaseMailbox() when
+  // it is finished with the frame.
+  OnVideoFrameDecoded(VideoFrame frame,
+                      mojo.common.mojom.UnguessableToken? release_token);
 };