Delete "Net.UnspecResolvedIPv6" histogram

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>
@@ skipping 1617 matching lines @@
     // 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) {
     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) {
-            got_ipv6_address = true;
-            break;
-          }
-        }
-        UMA_HISTOGRAM_BOOLEAN("Net.UnspecResolvedIPv6", got_ipv6_address);
-      }
-    }
-
     if (dns_task_error_ != OK) {
       base::TimeDelta duration = base::TimeTicks::Now() - start_time;
       if (net_error == OK) {
         DNS_HISTOGRAM("AsyncDNS.FallbackSuccess", duration);
         if ((dns_task_error_ == ERR_NAME_NOT_RESOLVED) &&
             ResemblesNetBIOSName(key_.hostname)) {
           UmaAsyncDnsResolveStatus(RESOLVE_STATUS_SUSPECT_NETBIOS);
         } else {
           UmaAsyncDnsResolveStatus(RESOLVE_STATUS_PROC_SUCCESS);
         }
@@ skipping 378 matching lines @@
     NetLog* net_log,
     scoped_refptr<base::TaskRunner> worker_task_runner)
     : max_queued_jobs_(0),
       proc_params_(NULL, options.max_retry_attempts),
       net_log_(net_log),
       received_dns_config_(false),
       num_dns_failures_(0),
       assume_ipv6_failure_on_wifi_(false),
       use_local_ipv6_(false),
       last_ipv6_probe_result_(true),
-      resolved_known_ipv6_hostname_(false),
       additional_resolver_flags_(0),
       fallback_to_proctask_(true),
       worker_task_runner_(std::move(worker_task_runner)),
       persist_initialized_(false),
       weak_ptr_factory_(this),
       probe_weak_ptr_factory_(this) {
   if (options.enable_caching)
     cache_ = HostCache::CreateDefaultCache();
 
   PrioritizedDispatcher::Limits job_limits = options.GetDispatcherLimits();
@@ skipping 460 matching lines @@
 
   for (auto it = jobs_.begin(); self.get() && it != jobs_.end();) {
     Job* job = it->second.get();
     ++it;
     // This could remove |job| from |jobs_|, but iterator will remain valid.
     job->ServeFromHosts();
   }
 }
 
 void HostResolverImpl::OnIPAddressChanged() {
-  resolved_known_ipv6_hostname_ = false;
   last_ipv6_probe_time_ = base::TimeTicks();
   // Abandon all ProbeJobs.
   probe_weak_ptr_factory_.InvalidateWeakPtrs();
   if (cache_.get()) {
     cache_->OnNetworkChange();
     cache_hit_callbacks_.clear();
   }
 #if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
   RunLoopbackProbeJob();
 #endif
@@ skipping 173 matching lines @@
   if (job_)
     job_->CancelRequest(this);
 }
 
 void HostResolverImpl::RequestImpl::ChangeRequestPriority(
     RequestPriority priority) {
   job_->ChangeRequestPriority(this, priority);
 }
 
 }  // namespace net