Store a stacktrace of PrefService destruction in PrefChangeRegistrar

base/prefs/pref_service.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 "base/prefs/pref_service.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
+// TODO(battre): Delete this. See crbug.com/373435.
+#include "base/debug/stack_trace.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/prefs/default_pref_store.h"
 #include "base/prefs/pref_notifier_impl.h"
 #include "base/prefs/pref_registry.h"
 #include "base/prefs/pref_value_store.h"
 #include "base/stl_util.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 32 matching lines @@
       user_pref_store_(user_prefs),
       read_error_callback_(read_error_callback) {
   pref_notifier_->SetPrefService(this);
 
   InitFromStorage(async);
 }
 
 PrefService::~PrefService() {
   DCHECK(CalledOnValidThread());
 
+  // TODO(battre): Remove the following code. It's purpose is to understand
+  // whether a crash in PrefChangeRegistrar::~PrefChangeRegistrar() is caused
+  // by a PrefService already being dead. See crbug.com/373435.
+  std::string stack_trace = base::debug::StackTrace().ToString();
+  static_cast<PrefNotifier*>(pref_notifier_.get())
+      ->BroadcastPrefServiceDestructionTrace(stack_trace);
+
   // Reset pointers so accesses after destruction reliably crash.
   pref_value_store_.reset();
   pref_registry_ = NULL;
   user_pref_store_ = NULL;
   pref_notifier_.reset();
 }
 
 void PrefService::InitFromStorage(bool async) {
   if (user_pref_store_->IsInitializationComplete()) {
     read_error_callback_.Run(user_pref_store_->GetReadError());
@@ skipping 474 matching lines @@
       DCHECK(found_value->IsType(default_type));
       return found_value;
     } else {
       // Every registered preference has at least a default value.
       NOTREACHED() << "no valid value found for registered pref " << path;
     }
   }
 
   return NULL;
 }