Implemented new fence syncs which replaces the old sync points.

gpu/command_buffer/client/gpu_control.h

 // Copyright 2014 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.
 
 #ifndef GPU_COMMAND_BUFFER_CLIENT_GPU_CONTROL_H_
 #define GPU_COMMAND_BUFFER_CLIENT_GPU_CONTROL_H_
 
 #include <stdint.h>
 
 #include <vector>
@@ skipping 78 matching lines @@
   // Returns true if the channel to the Gpu is lost. When true, all contexts
   // should be considered as lost.
   virtual bool IsGpuChannelLost() = 0;
 
   // The namespace and command buffer ID forms a unique pair for all existing
   // GpuControl (on client) and matches for the corresponding command buffer
   // (on server) in a single server process.
   virtual CommandBufferNamespace GetNamespaceID() const = 0;
   virtual uint64_t GetCommandBufferID() const = 0;
 
+  // Fence Syncs use release counters at a context level, these fence syncs
+  // need to be flushed before they can be shared with other contexts across
+  // channels. Subclasses should implement these functions and take care of
+  // figuring out when a fence sync has been flushed.
+  virtual uint64_t GenerateFenceSyncRelease() = 0;
+  virtual bool IsFenceSyncRelease(uint64_t release) = 0;
+  virtual bool IsFenceSyncFlushed(uint64_t release) = 0;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(GpuControl);
 };
 
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_CLIENT_GPU_CONTROL_H_