bluetooth: guard adapter_ in destructor

chrome/browser/ui/webui/options2/chromeos/bluetooth_options_handler2.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 "chrome/browser/ui/webui/options2/chromeos/bluetooth_options_handler2.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/utf_string_conversions.h"
 #include "base/values.h"
@@ skipping 41 matching lines @@
 
 BluetoothOptionsHandler::BluetoothOptionsHandler() : weak_ptr_factory_(this) {
 }
 
 BluetoothOptionsHandler::~BluetoothOptionsHandler() {
   if (!CommandLine::ForCurrentProcess()
       ->HasSwitch(switches::kEnableBluetooth)) {
     return;
   }
 
-  adapter_->RemoveObserver(this);
+  if (adapter_.get())

[James Hawkins, 2012/03/15 17:19:07]

Optional nit: You can leave off the .get().

+    adapter_->RemoveObserver(this);
 }
 
 void BluetoothOptionsHandler::GetLocalizedValues(
     DictionaryValue* localized_strings) {
   DCHECK(localized_strings);
   localized_strings->SetString("bluetooth",
       l10n_util::GetStringUTF16(IDS_OPTIONS_SETTINGS_SECTION_TITLE_BLUETOOTH));
   localized_strings->SetString("disableBluetooth",
       l10n_util::GetStringUTF16(IDS_OPTIONS_SETTINGS_BLUETOOTH_DISABLE));
   localized_strings->SetString("enableBluetooth",
@@ skipping 333 matching lines @@
 void BluetoothOptionsHandler::ErrorCallback() {
   // TODO(keybuk): we don't get any form of error response from dbus::
   // yet, other than an error occurred. I'm going to fix that, then this
   // gets replaced by genuine error information from the method which we
   // can act on, rather than a debug log statement.
   DVLOG(1) << "Failed.";
 }
 
 }  // namespace options2
 }  // namespace chromeos