Change mojo geometry structs from using type converters to StructTraits.

ash/sysui/keyboard_ui_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 ASH_SYSUI_KEYBOARD_UI_MUS_H_
 #define ASH_SYSUI_KEYBOARD_UI_MUS_H_
 
 #include <memory>
 
 #include "ash/keyboard/keyboard_ui.h"
@@ skipping 17 matching lines @@
 
   // KeyboardUI:
   void Hide() override;
   void Show() override;
   bool IsEnabled() override;
 
   // keyboard::mojom::KeyboardObserver:
   void OnKeyboardStateChanged(bool is_enabled,
                               bool is_visible,
                               uint64_t display_id,
-                              mojo::RectPtr bounds) override;
+                              const gfx::Rect& bounds) override;
 
  private:
   bool is_enabled_;
 
   keyboard::mojom::KeyboardPtr keyboard_;
   mojo::Binding<keyboard::mojom::KeyboardObserver> observer_binding_;
 
   DISALLOW_COPY_AND_ASSIGN(KeyboardUIMus);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SYSUI_KEYBOARD_UI_MUS_H_