Revert 113321 (speculative revert for http://crbug.com/106657 and a few other problems)

chrome/browser/chrome_browser_main.cc

 // Copyright (c) 2011 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 <algorithm>
 #include <string>
 #include <vector>
 
@@ skipping 1231 matching lines @@
   } else {
     browser_process_.reset(new BrowserProcessImpl(parsed_command_line()));
   }
 
   if (parsed_command_line().HasSwitch(switches::kEnableProfiling)) {
     // User wants to override default tracking status.
     std::string flag =
       parsed_command_line().GetSwitchValueASCII(switches::kEnableProfiling);
     bool enabled = flag.compare("0") != 0;
     tracked_objects::ThreadData::InitializeAndSetTrackingStatus(enabled);
+  } else {
+#if defined(OS_WIN)
+    // TODO(jar) 103209: Temporarilly default to disable for XP.
+    if (base::win::GetVersion() <= base::win::VERSION_XP)
+      tracked_objects::ThreadData::InitializeAndSetTrackingStatus(false);
+#endif  // OS_WIN
   }
 
   // This forces the TabCloseableStateWatcher to be created and, on chromeos,
   // register for the notifications it needs to track the closeable state of
   // tabs.
   g_browser_process->tab_closeable_state_watcher();
 
   local_state_ = InitializeLocalState(parsed_command_line(),
                                       is_first_run_);
 
@@ skipping 887 matching lines @@
   if (env->GetVar(chrome::kPreReadEnvironmentVariable, &pre_read) &&
       (pre_read == "0" || pre_read == "1")) {
     std::string uma_name(name);
     uma_name += "_PreRead";
     uma_name += pre_read == "1" ? "Enabled" : "Disabled";
     AddPreReadHistogramTime(uma_name.c_str(), time);
   }
 #endif
 #endif
 }