chromeos: Fix crash when clicking on networking menu under mash

ash/mus/window_manager_application.cc

Index: ash/mus/window_manager_application.cc
diff --git a/ash/mus/window_manager_application.cc b/ash/mus/window_manager_application.cc
index 3594bf3237f3dd370aa89b1249dc03962e1df08f..2594871853f8089ff788e686d2a708825236d9f4 100644
--- a/ash/mus/window_manager_application.cc
+++ b/ash/mus/window_manager_application.cc
@@ -95,16 +95,21 @@ void WindowManagerApplication::InitializeComponents(bool init_network_handler) {
   message_center::MessageCenter::Initialize();
 
   // Must occur after mojo::ApplicationRunner has initialized AtExitManager, but
-  // before WindowManager::Init().
-  chromeos::DBusThreadManager::Initialize(
-      chromeos::DBusThreadManager::PROCESS_ASH);
+  // before WindowManager::Init(). Tests might initialize their own instance.
+  if (!chromeos::DBusThreadManager::IsInitialized()) {
+    chromeos::DBusThreadManager::Initialize(
+        chromeos::DBusThreadManager::PROCESS_ASH);
+    dbus_thread_manager_initialized_ = true;
+  }
 
   // See ChromeBrowserMainPartsChromeos for ordering details.
   bluez::BluezDBusManager::Initialize(
       chromeos::DBusThreadManager::Get()->GetSystemBus(),
       chromeos::DBusThreadManager::Get()->IsUsingFakes());
-  if (init_network_handler)
+  if (init_network_handler && !chromeos::NetworkHandler::IsInitialized()) {
     chromeos::NetworkHandler::Initialize();
+    network_handler_initialized_ = true;
+  }
   network_connect_delegate_.reset(new NetworkConnectDelegateMus());
   chromeos::NetworkConnect::Initialize(network_connect_delegate_.get());
   // TODO(jamescook): Initialize real audio handler.
@@ -117,11 +122,12 @@ void WindowManagerApplication::ShutdownComponents() {
   chromeos::NetworkConnect::Shutdown();
   network_connect_delegate_.reset();
   // We may not have started the NetworkHandler.
-  if (chromeos::NetworkHandler::IsInitialized())
+  if (network_handler_initialized_)
     chromeos::NetworkHandler::Shutdown();
   device::BluetoothAdapterFactory::Shutdown();
   bluez::BluezDBusManager::Shutdown();
-  chromeos::DBusThreadManager::Shutdown();
+  if (dbus_thread_manager_initialized_)
+    chromeos::DBusThreadManager::Shutdown();
   message_center::MessageCenter::Shutdown();
 }