Update from https://crrev.com/306655

net/dns/host_resolver_impl.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/dns/host_resolver_impl.h"
 
 #if defined(OS_WIN)
 #include <Winsock2.h>
 #elif defined(OS_POSIX)
 #include <netdb.h>
 #endif
 
 #include <cmath>
 #include <utility>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/debug/debugger.h"
 #include "base/debug/stack_trace.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
+#include "base/profiler/scoped_tracker.h"
 #include "base/stl_util.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/threading/worker_pool.h"
 #include "base/time/time.h"
 #include "base/values.h"
 #include "net/base/address_family.h"
 #include "net/base/address_list.h"
 #include "net/base/dns_reloader.h"
 #include "net/base/dns_util.h"
@@ skipping 436 matching lines @@
   }
 
   void set_job(Job* job) {
     DCHECK(job);
     // Identify which job the request is waiting on.
     job_ = job;
   }
 
   // Prepare final AddressList and call completion callback.
   void OnComplete(int error, const AddressList& addr_list) {
+    // TODO(vadimt): Remove ScopedTracker below once crbug.com/436634 is fixed.
+    tracked_objects::ScopedTracker tracking_profile(
+        FROM_HERE_WITH_EXPLICIT_FUNCTION(
+            "436634 HostResolverImpl::Request::OnComplete"));
+
     DCHECK(!was_canceled());
     if (error == OK)
       *addresses_ = EnsurePortOnAddressList(addr_list, info_.port());
     CompletionCallback callback = callback_;
     MarkAsCanceled();
     callback.Run(error);
   }
 
   Job* job() const {
     return job_;
@@ skipping 179 matching lines @@
     params_.unresponsive_delay *= params_.retry_factor;
     StartLookupAttempt();
   }
 
   // Callback for when DoLookup() completes (runs on origin thread).
   void OnLookupComplete(const AddressList& results,
                         const base::TimeTicks& start_time,
                         const uint32 attempt_number,
                         int error,
                         const int os_error) {
+    // TODO(vadimt): Remove ScopedTracker below once crbug.com/436634 is fixed.
+    tracked_objects::ScopedTracker tracking_profile1(
+        FROM_HERE_WITH_EXPLICIT_FUNCTION(
+            "436634 HostResolverImpl::ProcTask::OnLookupComplete1"));
+
     DCHECK(origin_loop_->BelongsToCurrentThread());
     // If results are empty, we should return an error.
     bool empty_list_on_ok = (error == OK && results.empty());
     UMA_HISTOGRAM_BOOLEAN("DNS.EmptyAddressListAndNoError", empty_list_on_ok);
     if (empty_list_on_ok)
       error = ERR_NAME_NOT_RESOLVED;
 
     bool was_retry_attempt = attempt_number > 1;
 
     // Ideally the following code would be part of host_resolver_proc.cc,
@@ skipping 41 matching lines @@
 
     if (error != OK) {
       net_log_callback = base::Bind(&NetLogProcTaskFailedCallback,
                                     0, error, os_error);
     } else {
       net_log_callback = results_.CreateNetLogCallback();
     }
     net_log_.EndEvent(NetLog::TYPE_HOST_RESOLVER_IMPL_PROC_TASK,
                       net_log_callback);
 
+    // TODO(vadimt): Remove ScopedTracker below once crbug.com/436634 is fixed.
+    tracked_objects::ScopedTracker tracking_profile2(
+        FROM_HERE_WITH_EXPLICIT_FUNCTION(
+            "436634 HostResolverImpl::ProcTask::OnLookupComplete2"));
+
     callback_.Run(error, results_);
   }
 
   void RecordPerformanceHistograms(const base::TimeTicks& start_time,
                                    const int error,
                                    const int os_error) const {
     DCHECK(origin_loop_->BelongsToCurrentThread());
     enum Category {  // Used in UMA_HISTOGRAM_ENUMERATION.
       RESOLVE_SUCCESS,
       RESOLVE_FAIL,
@@ skipping 710 matching lines @@
       proc_task_->set_had_non_speculative_request();
     // Start() could be called from within Resolve(), hence it must NOT directly
     // call OnProcTaskComplete, for example, on synchronous failure.
     proc_task_->Start();
   }
 
   // Called by ProcTask when it completes.
   void OnProcTaskComplete(base::TimeTicks start_time,
                           int net_error,
                           const AddressList& addr_list) {
+    // TODO(vadimt): Remove ScopedTracker below once crbug.com/436634 is fixed.
+    tracked_objects::ScopedTracker tracking_profile(
+        FROM_HERE_WITH_EXPLICIT_FUNCTION(
+            "436634 HostResolverImpl::Job::OnProcTaskComplete"));
+
     DCHECK(is_proc_running());
 
     if (!resolver_->resolved_known_ipv6_hostname_ &&
         net_error == OK &&
         key_.address_family == ADDRESS_FAMILY_UNSPECIFIED) {
       if (key_.hostname == "www.google.com") {
         resolver_->resolved_known_ipv6_hostname_ = true;
         bool got_ipv6_address = false;
         for (size_t i = 0; i < addr_list.size(); ++i) {
           if (addr_list[i].GetFamily() == ADDRESS_FAMILY_IPV6) {
@@ skipping 129 matching lines @@
     // We already have a job slot at the dispatcher, so if the second
     // transaction hasn't started, reuse it now instead of waiting in the queue
     // for the second slot.
     if (dns_task_->needs_another_transaction())
       dns_task_->StartSecondTransaction();
   }
 
   // Performs Job's last rites. Completes all Requests. Deletes this.
   void CompleteRequests(const HostCache::Entry& entry,
                         base::TimeDelta ttl) {
+    // TODO(vadimt): Remove ScopedTracker below once crbug.com/436634 is fixed.
+    tracked_objects::ScopedTracker tracking_profile1(
+        FROM_HERE_WITH_EXPLICIT_FUNCTION(
+            "436634 HostResolverImpl::Job::CompleteRequests1"));
+
     CHECK(resolver_.get());
 
     // This job must be removed from resolver's |jobs_| now to make room for a
     // new job with the same key in case one of the OnComplete callbacks decides
     // to spawn one. Consequently, the job deletes itself when CompleteRequests
     // is done.
     scoped_ptr<Job> self_deleter(this);
 
     resolver_->RemoveJob(this);
 
@@ skipping 29 matching lines @@
       // configuration.
       UMA_HISTOGRAM_BOOLEAN("AsyncDNS.HaveDnsConfig",
                             resolver_->received_dns_config_);
     }
 
     bool did_complete = (entry.error != ERR_NETWORK_CHANGED) &&
                         (entry.error != ERR_HOST_RESOLVER_QUEUE_TOO_LARGE);
     if (did_complete)
       resolver_->CacheResult(key_, entry, ttl);
 
+    // TODO(vadimt): Remove ScopedTracker below once crbug.com/436634 is fixed.
+    tracked_objects::ScopedTracker tracking_profile2(
+        FROM_HERE_WITH_EXPLICIT_FUNCTION(
+            "436634 HostResolverImpl::Job::CompleteRequests2"));
+
     // Complete all of the requests that were attached to the job.
     for (RequestsList::const_iterator it = requests_.begin();
          it != requests_.end(); ++it) {
       Request* req = *it;
 
       if (req->was_canceled())
         continue;
 
       DCHECK_EQ(this, req->job());
       // Update the net log and notify registered observers.
@@ skipping 647 matching lines @@
     dns_client_->SetConfig(dns_config);
     num_dns_failures_ = 0;
     if (dns_client_->GetConfig())
       UMA_HISTOGRAM_BOOLEAN("AsyncDNS.DnsClientEnabled", true);
   }
 
   AbortDnsTasks();
 }
 
 }  // namespace net