aura: Remove WindowTreeHost::OnDeviceScaleFactorChanged.

ui/aura/window_tree_host_win.h

 // Copyright (c) 2012 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_WINDOW_TREE_HOST_WIN_H_
 #define UI_AURA_WINDOW_TREE_HOST_WIN_H_
 
 #include "base/compiler_specific.h"
 #include "ui/aura/aura_export.h"
 #include "ui/aura/window_tree_host.h"
@@ skipping 15 matching lines @@
   virtual void Hide() OVERRIDE;
   virtual gfx::Rect GetBounds() const OVERRIDE;
   virtual void SetBounds(const gfx::Rect& bounds) OVERRIDE;
   virtual gfx::Point GetLocationOnNativeScreen() const OVERRIDE;
   virtual void SetCapture() OVERRIDE;
   virtual void ReleaseCapture() OVERRIDE;
   virtual void SetCursorNative(gfx::NativeCursor cursor) OVERRIDE;
   virtual void MoveCursorToNative(const gfx::Point& location) OVERRIDE;
   virtual void OnCursorVisibilityChangedNative(bool show) OVERRIDE;
   virtual void PostNativeEvent(const base::NativeEvent& native_event) OVERRIDE;
-  virtual void OnDeviceScaleFactorChanged(float device_scale_factor) OVERRIDE;
 
   // ui::EventSource:
   virtual ui::EventProcessor* GetEventProcessor() OVERRIDE;
 
  private:
   CR_BEGIN_MSG_MAP_EX(WindowTreeHostWin)
     // Range handlers must go first!
     CR_MESSAGE_RANGE_HANDLER_EX(WM_MOUSEFIRST, WM_MOUSELAST, OnMouseRange)
     CR_MESSAGE_RANGE_HANDLER_EX(WM_NCMOUSEMOVE,
                                 WM_NCXBUTTONDBLCLK,
@@ skipping 37 matching lines @@
 // Set true to let WindowTreeHostWin use a popup window
 // with no frame/title so that the window size and test's
 // expectations matches.
 AURA_EXPORT void SetUsePopupAsRootWindowForTest(bool use);
 
 }  // namespace
 
 }  // namespace aura
 
 #endif  // UI_AURA_WINDOW_TREE_HOST_WIN_H_