mojo: first take on removing mojo_main_{chromium,standalone}.

mojo/examples/echo/echo_service.cc

 // 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.
 
 #include "mojo/examples/echo/echo_service.mojom.h"
+#include "mojo/public/c/system/main.h"
 #include "mojo/public/cpp/application/application_connection.h"
 #include "mojo/public/cpp/application/application_delegate.h"
+#include "mojo/public/cpp/application/application_runner.h"
 #include "mojo/public/cpp/application/interface_factory_impl.h"
 
 namespace mojo {
 namespace examples {
 
 class EchoServiceImpl : public InterfaceImpl<EchoService> {
  public:
   virtual void EchoString(
       const String& value,
       const Callback<void(String)>& callback) MOJO_OVERRIDE {
     callback.Run(value);
   }
 };
 
 class EchoServiceDelegate : public ApplicationDelegate {
  public:
   virtual bool ConfigureIncomingConnection(ApplicationConnection* connection)
       MOJO_OVERRIDE {
     connection->AddService(&echo_service_factory_);
     return true;
   }
 
  private:
   InterfaceFactoryImpl<EchoServiceImpl> echo_service_factory_;
 };
 
 }  // namespace examples
+}  // namespace mojo
 
-// static
-ApplicationDelegate* ApplicationDelegate::Create() {
-  return new examples::EchoServiceDelegate();
+MojoResult MojoMain(MojoHandle shell_handle) {
+  mojo::ApplicationRunner runner(new mojo::examples::EchoServiceDelegate);
+  return runner.Run(shell_handle);
 }
-
-}  // namespace mojo