aw: Fix FBO restore in webview functor

android_webview/browser/surfaces_instance.h

Index: android_webview/browser/surfaces_instance.h
diff --git a/android_webview/browser/surfaces_instance.h b/android_webview/browser/surfaces_instance.h
index d036eef714f5cd41a8eb2fc0ad57dcc50bd02058..f2dbfe6bca6451c08cf01888513bb9b3b0bfefc6 100644
--- a/android_webview/browser/surfaces_instance.h
+++ b/android_webview/browser/surfaces_instance.h
@@ -40,7 +40,6 @@ class SurfacesInstance : public base::RefCounted<SurfacesInstance>,
 
   uint32_t AllocateSurfaceClientId();
   cc::SurfaceManager* GetSurfaceManager();
-  void SetBackingFrameBufferObject(int framebuffer_binding_ext);
 
   void DrawAndSwap(const gfx::Size& viewport,
                    const gfx::Rect& clip,
@@ -73,7 +72,6 @@ class SurfacesInstance : public base::RefCounted<SurfacesInstance>,
 
   uint32_t next_surface_client_id_;
 
-  scoped_refptr<AwGLSurface> gl_surface_;
   std::unique_ptr<cc::SurfaceManager> surface_manager_;
   std::unique_ptr<cc::Display> display_;
   std::unique_ptr<cc::SurfaceIdAllocator> surface_id_allocator_;