Add a Mojo example apptest that runs in mojo_shell.

mojo/examples/test/example_service_impl.h

Index: mojo/examples/test/example_service_impl.h
diff --git a/mojo/examples/test/example_service_impl.h b/mojo/examples/test/example_service_impl.h
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index 0000000000000000000000000000000000000000..c160a33fc3df0129e12e6638fde2d673923f731f
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+++ b/mojo/examples/test/example_service_impl.h
@@ -0,0 +1,35 @@
+// 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_SERVICE_IMPL_H_
+#define MOJO_EXAMPLES_TEST_EXAMPLE_SERVICE_IMPL_H_
+
+#include "mojo/examples/test/example_service.mojom.h"
+#include "mojo/public/cpp/system/macros.h"
+
+namespace mojo {
+
+class ApplicationConnection;
+class ApplicationDelegate;
+
+class ExampleServiceImpl : public InterfaceImpl<ExampleService> {
+ public:
+ ExampleServiceImpl(ApplicationConnection* connection,
+                    ApplicationDelegate* delegate);

[Ben Goodger (Google), 2014/07/18 20:02:52]

You shouldn't need to pass the delegate, at least not as a ApplicationDelegate*.
The intent of the second parameter is to pass some global state into this
instance.

For every unique connection to your service there is one instance of this class.
The context parameter allows you to have some singleton state shared between all
connection instances.

[msw, 2014/07/21 18:58:22]

Cool, I removed this param the |this| argument from the
connection->AddService<ExampleServiceImpl>() call in
ExampleServiceApplication::ConfigureIncomingConnection().

+ virtual ~ExampleServiceImpl();
+
+ protected:
+  // InterfaceImpl<ExampleService> overrides.
+  virtual void Echo(
+    const String& to_echo,
+    const Callback<void(String)>& callback) MOJO_OVERRIDE;
+  virtual void Ping(uint16_t ping_value) MOJO_OVERRIDE;
+
+ private:
+  MOJO_DISALLOW_COPY_AND_ASSIGN(ExampleServiceImpl);
+};
+
+}  // namespace mojo
+
+#endif  // MOJO_EXAMPLES_TEST_EXAMPLE_SERVICE_IMPL_H_