Use Binding instead of InterfaceImpl for ExampleService.

examples/apptest/example_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_EXAMPLES_TEST_EXAMPLE_CLIENT_IMPL_H_
 #define MOJO_EXAMPLES_TEST_EXAMPLE_CLIENT_IMPL_H_
 
 #include "examples/apptest/example_service.mojom.h"
 #include "mojo/public/cpp/system/macros.h"
 
 namespace mojo {
 
-class ExampleClientImpl : public InterfaceImpl<ExampleClient> {
+class ExampleClientImpl : public ExampleClient {
  public:
   ExampleClientImpl();
-  virtual ~ExampleClientImpl();
+  ~ExampleClientImpl() override;
 
   int16_t last_pong_value() const { return last_pong_value_; }
 
-  // InterfaceImpl<ExampleClient> overrides.
-  virtual void Pong(uint16_t pong_value) override;
+  // ExampleClient overrides.
+  void Pong(uint16_t pong_value) override;
 
  private:
   int16_t last_pong_value_;
   MOJO_DISALLOW_COPY_AND_ASSIGN(ExampleClientImpl);
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_EXAMPLES_TEST_EXAMPLE_CLIENT_IMPL_H_