Revert of Reland "Added an extra sync token field for extra command buffer..."

content/common/gpu/client/gpu_channel_host.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 "content/common/gpu/client/gpu_channel_host.h"
 
 #include <algorithm>
 
 #include "base/atomic_sequence_num.h"
 #include "base/bind.h"
@@ skipping 144 matching lines @@
                                    latency_info.begin(), latency_info.end());
 
     if (do_flush)
       InternalFlush(&flush_info);
 
     return flush_id;
   }
   return 0;
 }
 
-void GpuChannelHost::FlushPendingStream(int32 stream_id) {
-  AutoLock lock(context_lock_);
-  auto flush_info_iter = stream_flush_info_.find(stream_id);
-  if (flush_info_iter == stream_flush_info_.end())
-    return;
-
-  StreamFlushInfo& flush_info = flush_info_iter->second;
-  if (flush_info.flush_pending)
-    InternalFlush(&flush_info);
-}
-
 void GpuChannelHost::InternalFlush(StreamFlushInfo* flush_info) {
   context_lock_.AssertAcquired();
   DCHECK(flush_info);
   DCHECK(flush_info->flush_pending);
   DCHECK_LT(flush_info->flushed_stream_flush_id, flush_info->flush_id);
   Send(new GpuCommandBufferMsg_AsyncFlush(
       flush_info->route_id, flush_info->put_offset, flush_info->flush_count,
       flush_info->latency_info));
   flush_info->latency_info.clear();
   flush_info->flush_pending = false;
@@ skipping 214 matching lines @@
 
 int32 GpuChannelHost::ReserveImageId() {
   return next_image_id_.GetNext();
 }
 
 int32 GpuChannelHost::GenerateRouteID() {
   return next_route_id_.GetNext();
 }
 
 int32 GpuChannelHost::GenerateStreamID() {
-  const int32 stream_id = next_stream_id_.GetNext();
-  DCHECK_NE(0, stream_id);
-  DCHECK_NE(kDefaultStreamId, stream_id);
-  return stream_id;
+  return next_stream_id_.GetNext();
 }
 
 uint32_t GpuChannelHost::ValidateFlushIDReachedServer(int32 stream_id,
                                                       bool force_validate) {
   // Store what flush ids we will be validating for all streams.
   base::hash_map<int32, uint32_t> validate_flushes;
   uint32_t flushed_stream_flush_id = 0;
   uint32_t verified_stream_flush_id = 0;
   {
     AutoLock lock(context_lock_);
@@ skipping 117 matching lines @@
 
   listeners_.clear();
 }
 
 bool GpuChannelHost::MessageFilter::IsLost() const {
   AutoLock lock(lock_);
   return lost_;
 }
 
 }  // namespace content