Add more instrumentation for tracking jank in ProxyService creation.

net/proxy/proxy_config_service_win.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 "net/proxy/proxy_config_service_win.h"
 
 #include <windows.h>
 #include <winhttp.h>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/profiler/scoped_tracker.h"
 #include "base/stl_util.h"
+#include "base/strings/string_tokenizer.h"
 #include "base/strings/string_util.h"
-#include "base/strings/string_tokenizer.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/win/registry.h"
 #include "base/win/scoped_handle.h"
 #include "net/base/net_errors.h"
 #include "net/proxy/proxy_config.h"
 
 #pragma comment(lib, "winhttp.lib")
 
 namespace net {
@@ skipping 28 matching lines @@
 
 void ProxyConfigServiceWin::AddObserver(Observer* observer) {
   // Lazily-initialize our registry watcher.
   StartWatchingRegistryForChanges();
 
   // Let the super-class do its work now.
   PollingProxyConfigService::AddObserver(observer);
 }
 
 void ProxyConfigServiceWin::StartWatchingRegistryForChanges() {
+  // TODO(eroman): Remove once crbug.com/454983 is solved.
+  tracked_objects::ScopedTracker tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "454983 ProxyConfigServiceWin::StartWatchingRegistryForChanges"));
+
   if (!keys_to_watch_.empty())
     return;  // Already initialized.
 
   // The registry functions below will end up going to disk.  Do this on another
   // thread to avoid slowing the IO thread.  http://crbug.com/61453
   base::ThreadRestrictions::ScopedAllowIO allow_io;
 
   // There are a number of different places where proxy settings can live
   // in the registry. In some cases it appears in a binary value, in other
   // cases string values. Furthermore winhttp and wininet appear to have
@@ skipping 88 matching lines @@
       std::string bypass_url_domain = proxy_server_bypass_list.token();
       config->proxy_rules().bypass_rules.AddRuleFromString(bypass_url_domain);
     }
   }
   if (ie_config.lpszAutoConfigUrl)
     config->set_pac_url(GURL(ie_config.lpszAutoConfigUrl));
   config->set_source(PROXY_CONFIG_SOURCE_SYSTEM);
 }
 
 }  // namespace net