Avoid creating sync token when only change is new hardware video frame.

media/filters/gpu_video_decoder.cc

 // 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.
 
 #include "media/filters/gpu_video_decoder.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 478 matching lines @@
     return;
   }
 
   pixel_format_ = format;
   if (!factories_->CreateTextures(count * textures_per_buffer, size,
                                   &texture_ids, &texture_mailboxes,
                                   decoder_texture_target_)) {
     NotifyError(VideoDecodeAccelerator::PLATFORM_FAILURE);
     return;
   }
+  sync_token_ = factories_->CreateSyncToken();
   DCHECK_EQ(count * textures_per_buffer, texture_ids.size());
   DCHECK_EQ(count * textures_per_buffer, texture_mailboxes.size());
 
   if (!vda_)
     return;
 
   std::vector<PictureBuffer> picture_buffers;
   size_t index = 0;
   for (size_t i = 0; i < count; ++i) {
     PictureBuffer::TextureIds ids;
@@ skipping 80 matching lines @@
   if (!gfx::Rect(pb.size()).Contains(visible_rect)) {
     LOG(WARNING) << "Visible size " << visible_rect.ToString()
                  << " is larger than coded size " << pb.size().ToString();
     visible_rect = gfx::Rect(pb.size());
   }
 
   DCHECK(decoder_texture_target_);
 
   gpu::MailboxHolder mailbox_holders[VideoFrame::kMaxPlanes];
   for (size_t i = 0; i < pb.texture_ids().size(); ++i) {
-    mailbox_holders[i] = gpu::MailboxHolder(
-        pb.texture_mailbox(i), gpu::SyncToken(), decoder_texture_target_);
+    mailbox_holders[i] = gpu::MailboxHolder(pb.texture_mailbox(i), sync_token_,
+                                            decoder_texture_target_);
   }
 
   scoped_refptr<VideoFrame> frame(VideoFrame::WrapNativeTextures(
       pixel_format_, mailbox_holders,
       base::Bind(&ReleaseMailboxTrampoline, factories_->GetTaskRunner(),
                  base::Bind(&GpuVideoDecoder::ReleaseMailbox,
                             weak_factory_.GetWeakPtr(), factories_,
                             picture.picture_buffer_id(), pb.texture_ids())),
       pb.size(), visible_rect, natural_size, timestamp));
   if (!frame) {
@@ skipping 213 matching lines @@
   }
   return false;
 }
 
 void GpuVideoDecoder::DCheckGpuVideoAcceleratorFactoriesTaskRunnerIsCurrent()
     const {
   DCHECK(factories_->GetTaskRunner()->BelongsToCurrentThread());
 }
 
 }  // namespace media