Remove WmLookup.

ash/mus/window_manager.cc

Index: ash/mus/window_manager.cc
diff --git a/ash/mus/window_manager.cc b/ash/mus/window_manager.cc
index e80e7c883f8197fd686aaee9d9a35d37203032df..8818e3cbdd393d96889b57860a3bdf4eaa865c69 100644
--- a/ash/mus/window_manager.cc
+++ b/ash/mus/window_manager.cc
@@ -14,7 +14,6 @@
 #include "ash/common/wm_window.h"
 #include "ash/mus/accelerators/accelerator_handler.h"
 #include "ash/mus/accelerators/accelerator_ids.h"
-#include "ash/mus/bridge/wm_lookup_mus.h"
 #include "ash/mus/bridge/wm_shell_mus.h"
 #include "ash/mus/move_event_handler.h"
 #include "ash/mus/non_client_frame_controller.h"
@@ -120,8 +119,6 @@ void WindowManager::Init(
   window_manager_client_->SetFrameDecorationValues(
       std::move(frame_decoration_values));
 
-  lookup_.reset(new WmLookupMus);
-
   // Notify PointerWatcherEventRouter and CaptureSynchronizer that the capture
   // client has been set.
   aura::client::CaptureClient* capture_client = wm_state_->capture_controller();
@@ -260,8 +257,6 @@ void WindowManager::Shutdown() {
 
   Shell::DeleteInstance();
 
-  lookup_.reset();
-
   pointer_watcher_event_router_.reset();
 
   window_tree_client_.reset();