Implement a poor man's PostAfterStartupTask() function.

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 21 matching lines @@
 #include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/sys_info.h"
 #include "base/threading/platform_thread.h"
 #include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
 #include "base/values.h"
 #include "build/build_config.h"
 #include "cc/base/switches.h"
 #include "chrome/browser/about_flags.h"
+#include "chrome/browser/after_startup_task_utils.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_process_impl.h"
 #include "chrome/browser/browser_process_platform_part.h"
 #include "chrome/browser/browser_shutdown.h"
 #include "chrome/browser/chrome_browser_main_extra_parts.h"
 #include "chrome/browser/component_updater/cld_component_installer.h"
 #include "chrome/browser/component_updater/ev_whitelist_component_installer.h"
 #include "chrome/browser/component_updater/flash_component_installer.h"
 #include "chrome/browser/component_updater/recovery_component_installer.h"
 #include "chrome/browser/component_updater/supervised_user_whitelist_installer.h"
@@ skipping 1068 matching lines @@
 #endif  // !defined(OS_ANDROID)
 #if defined(ENABLE_WEBRTC)
   // Set up a task to delete old WebRTC log files for all profiles. Use a delay
   // to reduce the impact on startup time.
   BrowserThread::PostDelayedTask(
       BrowserThread::UI,
       FROM_HERE,
       base::Bind(&WebRtcLogUtil::DeleteOldWebRtcLogFilesForAllProfiles),
       base::TimeDelta::FromMinutes(1));
 #endif  // defined(ENABLE_WEBRTC)
+
+  // At this point, StartupBrowserCreator::Start has run creating initial
+  // browser windows and tabs, but no progress has been made in loading
+  // content as the main message loop hasn't started processing tasks yet.
+  // We setup to observe to the initial page load here to defer running
+  // task posted via PostAfterStartupTask until its complete.
+  AfterStartupTaskUtils::StartMonitoringStartup();
 }
 
 int ChromeBrowserMainParts::PreMainMessageLoopRunImpl() {
   TRACE_EVENT0("startup", "ChromeBrowserMainParts::PreMainMessageLoopRunImpl");
   SCOPED_UMA_HISTOGRAM_LONG_TIMER("Startup.PreMainMessageLoopRunImplLongTime");
   const base::TimeTicks start_time_step1 = base::TimeTicks::Now();
   // Android updates the metrics service dynamically depending on whether the
   // application is in the foreground or not. Do not start here.
 #if !defined(OS_ANDROID)
   // Now that the file thread has been started, start recording.
@@ skipping 613 matching lines @@
   chromeos::CrosSettings::Shutdown();
 #endif  // defined(OS_CHROMEOS)
 #endif  // defined(OS_ANDROID)
 }
 
 // Public members:
 
 void ChromeBrowserMainParts::AddParts(ChromeBrowserMainExtraParts* parts) {
   chrome_extra_parts_.push_back(parts);
 }