Store a stacktrace of PrefService destruction in PrefChangeRegistrar

base/prefs/pref_service.cc

Index: base/prefs/pref_service.cc
diff --git a/base/prefs/pref_service.cc b/base/prefs/pref_service.cc
index a8e56d0b370680f9400e8432014d08b357fc4179..bdc0b399beadec4efabc092e2bb5d2c18ab2bcb8 100644
--- a/base/prefs/pref_service.cc
+++ b/base/prefs/pref_service.cc
@@ -7,6 +7,8 @@
 #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"
@@ -59,6 +61,13 @@ PrefService::PrefService(
 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;