Revert of CHECK that the RendererCompositorFrameSink has been detached

content/renderer/gpu/renderer_compositor_frame_sink.h

 // 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.
 
 #ifndef CONTENT_RENDERER_GPU_RENDERER_COMPOSITOR_FRAME_SINK_H_
 #define CONTENT_RENDERER_GPU_RENDERER_COMPOSITOR_FRAME_SINK_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 124 matching lines @@
     bool has_transparent_background;
 #endif
   } current_frame_data_;
 
   base::ThreadChecker thread_checker_;
 
   cc::mojom::MojoCompositorFrameSinkPtr sink_;
   cc::mojom::MojoCompositorFrameSinkPtrInfo sink_ptr_info_;
   cc::mojom::MojoCompositorFrameSinkClientRequest sink_client_request_;
   mojo::Binding<cc::mojom::MojoCompositorFrameSinkClient> sink_client_binding_;
-
-  bool bound_ = false;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_GPU_RENDERER_COMPOSITOR_FRAME_SINK_H_