gpu: Remove Echo and SwapCompletion GL interfacess

mojo/gles2/command_buffer_client_impl.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 MOJO_GLES2_COMMAND_BUFFER_CLIENT_IMPL_H_
 #define MOJO_GLES2_COMMAND_BUFFER_CLIENT_IMPL_H_
 
 #include <map>
 
 #include "base/macros.h"
@@ skipping 50 matching lines @@
                                                       int32* id) override;
   virtual void DestroyGpuMemoryBuffer(int32 id) override;
   virtual uint32 InsertSyncPoint() override;
   virtual uint32 InsertFutureSyncPoint() override;
   virtual void RetireSyncPoint(uint32 sync_point) override;
   virtual void SignalSyncPoint(uint32 sync_point,
                                const base::Closure& callback) override;
   virtual void SignalQuery(uint32 query,
                            const base::Closure& callback) override;
   virtual void SetSurfaceVisible(bool visible) override;
-  virtual void Echo(const base::Closure& callback) override;
   virtual uint32 CreateStreamTexture(uint32 texture_id) override;
 
  private:
   class SyncClientImpl;
 
   // CommandBufferClient implementation:
   virtual void DidDestroy() override;
   virtual void LostContext(int32_t lost_reason) override;
 
   // ErrorHandler implementation:
@@ skipping 14 matching lines @@
   int32 last_put_offset_;
   int32 next_transfer_buffer_id_;
 
   const MojoAsyncWaiter* async_waiter_;
 };
 
 }  // gles2
 }  // mojo
 
 #endif  // MOJO_GLES2_COMMAND_BUFFER_CLIENT_IMPL_H_