Adding instrumentation to locate the source of jankiness.

net/url_request/url_request.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/url_request/url_request.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
@@ skipping 249 matching lines @@
 }
 
 int64 URLRequest::GetTotalReceivedBytes() const {
   if (!job_.get())
     return 0;
 
   return job_->GetTotalReceivedBytes();
 }
 
 LoadStateWithParam URLRequest::GetLoadState() const {
+  // TODO(pkasting): Remove ScopedTracker below once crbug.com/455952 is
+  // fixed.
+  tracked_objects::ScopedTracker tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION("455952 URLRequest::GetLoadState"));
   // The !blocked_by_.empty() check allows |this| to report it's blocked on a
   // delegate before it has been started.
   if (calling_delegate_ || !blocked_by_.empty()) {
     return LoadStateWithParam(
         LOAD_STATE_WAITING_FOR_DELEGATE,
         use_blocked_by_as_load_param_ ? base::UTF8ToUTF16(blocked_by_) :
                                         base::string16());
   }
   return LoadStateWithParam(job_.get() ? job_->GetLoadState() : LOAD_STATE_IDLE,
                             base::string16());
@@ skipping 934 matching lines @@
       new base::debug::StackTrace(NULL, 0);
   *stack_trace_copy = stack_trace;
   stack_trace_.reset(stack_trace_copy);
 }
 
 const base::debug::StackTrace* URLRequest::stack_trace() const {
   return stack_trace_.get();
 }
 
 }  // namespace net