Remove docked windows entirely in M59.

ui/views/mus/desktop_window_tree_host_mus.h

 // Copyright 2016 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_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_WINDOW_TREE_HOST_MUS_H_
 #define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_WINDOW_TREE_HOST_MUS_H_
 
 #include <memory>
 #include <set>
 
@@ skipping 29 matching lines @@
 
   // Called when the window was deleted on the server.
   void ServerDestroyedWindow() { CloseNow(); }
 
   // Controls whether the client area is automatically updated as necessary.
   void set_auto_update_client_area(bool value) {
     auto_update_client_area_ = value;
   }
 
  private:
-  bool IsDocked() const;
-
   void SendClientAreaToServer();
   void SendHitTestMaskToServer();
 
   // Helper function to get the scale factor.
   float GetScaleFactor() const;
 
   void SetBoundsInDIP(const gfx::Rect& bounds_in_dip);
 
   // Returns true if the client area should be set on this.
   bool ShouldSendClientAreaToServer() const;
@@ skipping 102 matching lines @@
 
   // Used so that Close() isn't immediate.
   base::WeakPtrFactory<DesktopWindowTreeHostMus> close_widget_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DesktopWindowTreeHostMus);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_WINDOW_TREE_HOST_MUS_H_