chromeos: fix focus for mushrome

ui/aura/mus/window_tree_client.h

 // Copyright 2014 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.
 
 #ifndef UI_AURA_MUS_WINDOW_TREE_CLIENT_H_
 #define UI_AURA_MUS_WINDOW_TREE_CLIENT_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 563 matching lines @@
 
   // A mapping to shared memory that is one 32 bit integer long. The window
   // server uses this to let us synchronously read the cursor location.
   mojo::ScopedSharedBufferMapping cursor_location_mapping_;
 
   base::ObserverList<WindowTreeClientObserver> observers_;
 
   std::unique_ptr<mojo::AssociatedBinding<ui::mojom::WindowManager>>
       window_manager_internal_;
   ui::mojom::WindowManagerClientAssociatedPtr window_manager_internal_client_;
+  // Normally the same as |window_manager_internal_client_|. Tests typically
+  // run without a service_manager::Connector, which means this (and
+  // |window_manager_internal_client_|) are null. Tests that need to test
+  // WindowManagerClient set this, but not |window_manager_internal_client_|.
+  ui::mojom::WindowManagerClient* window_manager_client_ = nullptr;
 
   bool has_pointer_watcher_ = false;
 
   // The current change id for the client.
   uint32_t current_move_loop_change_ = 0u;
 
   // Callback executed when a move loop initiated by PerformWindowMove() is
   // completed.
   base::Callback<void(bool)> on_current_move_finished_;
 
@@ skipping 24 matching lines @@
   gfx::Insets normal_client_area_insets_;
 
   base::WeakPtrFactory<WindowTreeClient> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowTreeClient);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_MUS_WINDOW_TREE_CLIENT_H_