Modify instrumentation for various jank bugs, mostly removing outdated sites.

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 469 matching lines @@
 void URLRequest::set_referrer_policy(ReferrerPolicy referrer_policy) {
   DCHECK(!is_pending_);
   referrer_policy_ = referrer_policy;
 }
 
 void URLRequest::set_delegate(Delegate* delegate) {
   delegate_ = delegate;
 }
 
 void URLRequest::Start() {
+  // TODO(pkasting): Remove ScopedTracker below once crbug.com/456327 is fixed.
+  tracked_objects::ScopedTracker tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION("456327 URLRequest::Start"));
+
   // Some values can be NULL, but the job factory must not be.
   DCHECK(context_->job_factory());
 
   // Anything that sets |blocked_by_| before start should have cleaned up after
   // itself.
   DCHECK(blocked_by_.empty());
 
   g_url_requests_started = true;
   response_info_.request_time = base::Time::Now();
 
@@ skipping 715 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