Add some trace points to mojo_shell for app lifetime

shell/context.cc

 // 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.
 
 #include "shell/context.h"
 
 #include <vector>
 
 #include "base/base_switches.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/lazy_instance.h"
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "base/path_service.h"
 #include "base/run_loop.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
+#include "base/trace_event/trace_event.h"
 #include "build/build_config.h"
 #include "mojo/common/trace_controller_impl.h"
 #include "mojo/common/tracing_impl.h"
 #include "mojo/edk/embedder/embedder.h"
 #include "mojo/edk/embedder/simple_platform_support.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 "services/tracing/tracing.mojom.h"
 #include "shell/application_manager/application_loader.h"
@@ skipping 196 matching lines @@
 
 void Context::SetCommandLineCWD(const base::FilePath& path) {
   command_line_cwd_ = AddTrailingSlashIfNeeded(FilePathToFileURL(path));
 }
 
 GURL Context::ResolveCommandLineURL(const std::string& path) {
   return command_line_cwd_.Resolve(path);
 }
 
 bool Context::Init() {
+  TRACE_EVENT0("mojo_shell", "Context::Init");
   const base::CommandLine& command_line =
       *base::CommandLine::ForCurrentProcess();
 
   if (command_line.HasSwitch(switches::kWaitForDebugger))
     base::debug::WaitForDebugger(60, true);
 
   EnsureEmbedderIsInitialized();
   task_runners_.reset(
       new TaskRunners(base::MessageLoop::current()->message_loop_proxy()));
 
@@ skipping 44 matching lines @@
       GURL("mojo:tracing"), GURL(""), nullptr,
       tracing_service_provider_ptr.Pass());
 
   if (listener_)
     listener_->WaitForListening();
 
   return true;
 }
 
 void Context::Shutdown() {
+  TRACE_EVENT0("mojo_shell", "Context::Shutdown");
   DCHECK_EQ(base::MessageLoop::current()->task_runner(),
             task_runners_->shell_runner());
   embedder::ShutdownIPCSupport();
   // We'll quit when we get OnShutdownComplete().
   base::MessageLoop::current()->Run();
 }
 
 void Context::OnApplicationError(const GURL& url) {
+  TRACE_EVENT1("mojo_shell", "Context::OnApplicationError", "url", url.spec());
   if (app_urls_.find(url) != app_urls_.end()) {
     app_urls_.erase(url);
     if (app_urls_.empty() && base::MessageLoop::current()->is_running()) {
       DCHECK_EQ(base::MessageLoop::current()->task_runner(),
                 task_runners_->shell_runner());
       base::MessageLoop::current()->Quit();
     }
   }
 }
 
@@ skipping 23 matching lines @@
 ScopedMessagePipeHandle Context::ConnectToServiceByName(
     const GURL& application_url,
     const std::string& service_name) {
   app_urls_.insert(application_url);
   return application_manager_.ConnectToServiceByName(application_url,
                                                      service_name).Pass();
 }
 
 }  // namespace shell
 }  // namespace mojo