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

mojo/examples/dbus_echo/dbus_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 "base/at_exit.h"
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "mojo/dbus/dbus_external_service.h"
 #include "mojo/embedder/channel_init.h"
 #include "mojo/embedder/embedder.h"
 #include "mojo/embedder/simple_platform_support.h"
+#include "mojo/examples/echo/echo_service.mojom.h"
 #include "mojo/public/cpp/environment/environment.h"
-#include "mojo/services/dbus_echo/echo.mojom.h"
 
 namespace {
-class EchoServiceImpl : public mojo::InterfaceImpl<mojo::EchoService> {
+class EchoServiceImpl
+    : public mojo::InterfaceImpl<mojo::examples::EchoService> {
  public:
   EchoServiceImpl() {}
   virtual ~EchoServiceImpl() {}
 
  protected:
-  virtual void Echo(
+  virtual void EchoString(
       const mojo::String& in_to_echo,
       const mojo::Callback<void(mojo::String)>& callback) OVERRIDE {
     DVLOG(1) << "Asked to echo " << in_to_echo;
     callback.Run(in_to_echo);
   }
 };
 
 const char kServiceName[] = "org.chromium.EchoService";
 }  // anonymous namespace
 
 int main(int argc, char** argv) {
   base::AtExitManager exit_manager;
   base::CommandLine::Init(argc, argv);
 
   logging::LoggingSettings settings;
   settings.logging_dest = logging::LOG_TO_SYSTEM_DEBUG_LOG;
   logging::InitLogging(settings);
-  logging::SetLogItems(false,    // Process ID
-                       false,    // Thread ID
-                       false,    // Timestamp
-                       false);   // Tick count
+  logging::SetLogItems(false,   // Process ID
+                       false,   // Thread ID
+                       false,   // Timestamp
+                       false);  // Tick count
 
   mojo::embedder::Init(scoped_ptr<mojo::embedder::PlatformSupport>(
       new mojo::embedder::SimplePlatformSupport()));
 
   base::MessageLoopForIO message_loop;
   base::RunLoop run_loop;
 
   mojo::DBusExternalService<EchoServiceImpl> echo_service(kServiceName);
   echo_service.Start();
 
   run_loop.Run();
   return 0;
 }