Fix potential crashes in NetworkHandler code

chrome/browser/chromeos/mobile/mobile_activator_unittest.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/chromeos/mobile/mobile_activator.h"
 
 #include <stddef.h>
 #include <utility>
 
 #include "base/macros.h"
@@ skipping 104 matching lines @@
                                       base::StringValue(shill::kTypeCellular));
   }
   ~MobileActivatorTest() override {}
 
  protected:
   void SetUp() override {
     DBusThreadManager::Initialize();
     NetworkHandler::Initialize();
   }
   void TearDown() override {
+    mobile_activator_.TerminateActivation();
     NetworkHandler::Shutdown();
     DBusThreadManager::Shutdown();
   }
 
   void set_activator_state(const MobileActivator::PlanActivationState state) {
     mobile_activator_.set_state_for_test(state);
   }
   void set_network_activation_type(const std::string& activation_type) {
     cellular_network_.activation_type_ = activation_type;
   }
@@ skipping 220 matching lines @@
   EXPECT_EQ(MobileActivator::PLAN_ACTIVATION_RECONNECTING,
             mobile_activator_.InvokePickNextState(&cellular_network_,
                                                   &error_description));
   set_activator_state(MobileActivator::PLAN_ACTIVATION_SHOWING_PAYMENT);
   EXPECT_EQ(MobileActivator::PLAN_ACTIVATION_RECONNECTING,
             mobile_activator_.InvokePickNextState(&cellular_network_,
                                                   &error_description));
 }
 
 }  // namespace chromeos