Remove redundant echo.mojom, verify non-nullables in echo_service.mojom

mojo/mojo_examples.gypi

 # Copyright 2013 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.
 
 {
   'targets': [
     {
       # GN version: //mojo/examples/echo:client
       'target_name': 'mojo_echo_client',
       'type': 'loadable_module',
@@ skipping 807 matching lines @@
     ['OS=="linux"', {
       'targets': [
         {
           'target_name': 'mojo_dbus_echo',
           'type': 'loadable_module',
           'dependencies': [
             '../base/base.gyp:base',
             'mojo_base.gyp:mojo_application_standalone',
             'mojo_base.gyp:mojo_cpp_bindings',
             'mojo_base.gyp:mojo_utility',
-            'mojo_echo_bindings',
+            'mojo_echo_service_bindings',
             '<(mojo_system_for_loadable_module)',
           ],
           'sources': [
             'examples/dbus_echo/dbus_echo_app.cc',
           ],
         },
+        {
+          'target_name': 'mojo_dbus_echo_service',
+          'type': 'executable',
+          'dependencies': [
+            '../base/base.gyp:base',
+            '../build/linux/system.gyp:dbus',
+            '../dbus/dbus.gyp:dbus',
+            'mojo_base.gyp:mojo_common_lib',
+            'mojo_base.gyp:mojo_system_impl',
+            'mojo_base.gyp:mojo_application_chromium',
+            'mojo_dbus_service',
+            'mojo_echo_service_bindings',
+          ],
+          'sources': [
+            'examples/dbus_echo/dbus_echo_service.cc',
+          ],
+        },
       ],
+
     }],
   ],
 }