Android media: VideoFrame should not store so many sync points.

cc/resources/video_resource_updater.cc

Index: cc/resources/video_resource_updater.cc
diff --git a/cc/resources/video_resource_updater.cc b/cc/resources/video_resource_updater.cc
index 1d93aebe3cce20f763da7349490d0f2a3f0d177b..bd38bfd9b7f8fb3a84bdec6d85fc46db1c1143d2 100644
--- a/cc/resources/video_resource_updater.cc
+++ b/cc/resources/video_resource_updater.cc
@@ -284,9 +284,11 @@ VideoFrameExternalResources VideoResourceUpdater::CreateForSoftwarePlanes(
 }
 
 static void ReturnTexture(const scoped_refptr<media::VideoFrame>& frame,
+                          ContextProvider* context_provider,
                           uint32 sync_point,
                           bool lost_resource) {
-  frame->AppendReleaseSyncPoint(sync_point);
+  frame->AppendReleaseSyncPoint(reinterpret_cast<uintptr_t>(context_provider),
+                                sync_point);

[dshwang, 2014/06/05 14:38:30]

reinterpret_cast is ugly but I could not find better way.
In detail,
we want to make VideoFrame keep sync point per graphic 3d client. Here
compositor uses ContextProvider as graphics 3d context, while WebMediaPlayer
uses WebGraphicsContext3D as graphics 3d context. Moreover, both don't have kind
of id() method.
More elegant solution might be to add id() method in WebGraphicsContext3D and
expose the method to ContextProvider in both in_process and command_buffer impl.
But it seems to be overkill.

[dshwang, 2014/06/05 14:53:19]

That's good question. If one client waits for sync point made by another client,
VideoFrame can keep only one latest sync point. It's not important to keep sync
points for all clients.
However, VideoResourceUpdater can not wait a sync point because
VideoResourceUpdater can not use any graphics 3d context at this point. If we
really want to do that, we need hack that ResouceProvider passes graphics 3d
context to this callback. IMO, it's more ugly.

 }
 
 VideoFrameExternalResources VideoResourceUpdater::CreateForHardwarePlanes(
@@ -322,8 +324,8 @@ VideoFrameExternalResources VideoResourceUpdater::CreateForHardwarePlanes(
       TextureMailbox(mailbox_holder->mailbox,
                      mailbox_holder->texture_target,
                      mailbox_holder->sync_point));
-  external_resources.release_callbacks.push_back(
-      base::Bind(&ReturnTexture, video_frame));
+  external_resources.release_callbacks.push_back(base::Bind(
+      &ReturnTexture, video_frame, base::Unretained(context_provider_)));
   return external_resources;
 }