gpu: Add GpuFence framework.

gpu/command_buffer/service/gles2_cmd_decoder_passthrough.h

Index: gpu/command_buffer/service/gles2_cmd_decoder_passthrough.h
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder_passthrough.h b/gpu/command_buffer/service/gles2_cmd_decoder_passthrough.h
index ea73c015b8af9b7c7a3c1977f8059dd493eb2b7c..2d0278d15430ec22203f6b1af77c79e8fb4ca85b 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder_passthrough.h
+++ b/gpu/command_buffer/service/gles2_cmd_decoder_passthrough.h
@@ -14,6 +14,7 @@
 #include "gpu/command_buffer/common/mailbox.h"
 #include "gpu/command_buffer/service/client_service_map.h"
 #include "gpu/command_buffer/service/context_group.h"
+#include "gpu/command_buffer/service/fence_manager.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder.h"
 #include "gpu/command_buffer/service/image_manager.h"
 #include "gpu/command_buffer/service/logger.h"
@@ -152,6 +153,9 @@ class GLES2DecoderPassthroughImpl : public GLES2Decoder {
   // Gets the ImageManager for this context.
   ImageManager* GetImageManager() override;
 
+  // Gets the FenceManager for this context.
+  FenceManager* GetFenceManager() override;
+
   // Returns false if there are no pending queries.
   bool HasPendingQueries() const override;
 
@@ -271,6 +275,7 @@ class GLES2DecoderPassthroughImpl : public GLES2Decoder {
 
   // Managers
   std::unique_ptr<ImageManager> image_manager_;
+  std::unique_ptr<FenceManager> fence_manager_;
 
   // The ContextGroup for this decoder uses to track resources.
   scoped_refptr<ContextGroup> group_;