Temporary commit to evaluate perf impact of prototype CPU profiler

chrome/browser/chrome_browser_main.cc

 // Copyright (c) 2012 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 "chrome/browser/chrome_browser_main.h"
 
 #include <set>
 #include <string>
 #include <vector>
 
@@ skipping 978 matching lines @@
   // Must be done after g_browser_process is constructed, before
   // SetupMetricsAndFieldTrials().
   chromeos::CrosSettings::Initialize();
 #endif
 
   // Now the command line has been mutated based on about:flags, we can setup
   // metrics and initialize field trials. The field trials are needed by
   // IOThread's initialization which happens in BrowserProcess:PreCreateThreads.
   SetupMetricsAndFieldTrials();
 
+  cpu_profiler_.Initialize(nullptr);
+
   // ChromeOS needs ResourceBundle::InitSharedInstance to be called before this.
   browser_process_->PreCreateThreads();
 
   return content::RESULT_CODE_NORMAL_EXIT;
 }
 
 void ChromeBrowserMainParts::PreMainMessageLoopRun() {
   TRACE_EVENT0("startup", "ChromeBrowserMainParts::PreMainMessageLoopRun");
   result_code_ = PreMainMessageLoopRunImpl();
 
@@ skipping 634 matching lines @@
 }
 
 void ChromeBrowserMainParts::PostMainMessageLoopRun() {
   TRACE_EVENT0("startup", "ChromeBrowserMainParts::PostMainMessageLoopRun");
 #if defined(OS_ANDROID)
   // Chrome on Android does not use default MessageLoop. It has its own
   // Android specific MessageLoop
   NOTREACHED();
 #else
 
+  cpu_profiler_.Stop();
+
   // Start watching for jank during shutdown. It gets disarmed when
   // |shutdown_watcher_| object is destructed.
   metrics::MetricsService::SetExecutionPhase(
       metrics::MetricsService::SHUTDOWN_TIMEBOMB_ARM,
       g_browser_process->local_state());
   shutdown_watcher_->Arm(base::TimeDelta::FromSeconds(300));
 
   // Disarm the startup hang detector time bomb if it is still Arm'ed.
   startup_watcher_->Disarm();
 
@@ skipping 47 matching lines @@
   chromeos::CrosSettings::Shutdown();
 #endif
 #endif
 }
 
 // Public members:
 
 void ChromeBrowserMainParts::AddParts(ChromeBrowserMainExtraParts* parts) {
   chrome_extra_parts_.push_back(parts);
 }