Add tracing service and make the shell+sky_viewer+services talk to it

mojo/services/native_viewport/main.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/macros.h"
 #include "base/message_loop/message_loop.h"
 #include "mojo/application/application_runner_chromium.h"
+#include "mojo/common/tracing_impl.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_impl.h"
 #include "mojo/public/cpp/application/interface_factory_impl.h"
 #include "mojo/services/gles2/gpu_impl.h"
 #include "mojo/services/native_viewport/native_viewport_impl.h"
 #include "mojo/services/public/cpp/native_viewport/args.h"
 #include "ui/gl/gl_surface.h"
 
 namespace mojo {
 
 class NativeViewportAppDelegate
     : public ApplicationDelegate,
       public InterfaceFactory<NativeViewport>,
       public InterfaceFactory<Gpu> {
  public:
   NativeViewportAppDelegate() : is_headless_(false) {}
   ~NativeViewportAppDelegate() override {}
 
  private:
   // ApplicationDelegate implementation.
   void Initialize(ApplicationImpl* application) override {
     app_ = application;
 
+    TracingImpl::Create(application);
+
     if (app_->HasArg(kUseTestConfig))
       gfx::GLSurface::InitializeOneOffForTests();
     else if (app_->HasArg(kUseOSMesa))
       gfx::GLSurface::InitializeOneOff(gfx::kGLImplementationOSMesaGL);
     else
       gfx::GLSurface::InitializeOneOff();
 
     is_headless_ = app_->HasArg(kUseHeadlessConfig);
   }
 
@@ skipping 23 matching lines @@
   bool is_headless_;
   DISALLOW_COPY_AND_ASSIGN(NativeViewportAppDelegate);
 };
 }
 
 MojoResult MojoMain(MojoHandle shell_handle) {
   mojo::ApplicationRunnerChromium runner(new mojo::NativeViewportAppDelegate);
   runner.set_message_loop_type(base::MessageLoop::TYPE_UI);
   return runner.Run(shell_handle);
 }