aura: Remove WindowTreeHost::OnDeviceScaleFactorChanged.

ui/aura/window.cc

 // 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.
 
 #include "ui/aura/window.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 777 matching lines @@
   SetPropertyInternal(
       key, key, NULL, reinterpret_cast<int64>(value), 0);
 }
 
 void* Window::GetNativeWindowProperty(const char* key) const {
   return reinterpret_cast<void*>(GetPropertyInternal(key, 0));
 }
 
 void Window::OnDeviceScaleFactorChanged(float device_scale_factor) {
   ScopedCursorHider hider(this);
-  if (IsRootWindow())
-    host_->OnDeviceScaleFactorChanged(device_scale_factor);
   if (delegate_)
     delegate_->OnDeviceScaleFactorChanged(device_scale_factor);
 }
 
 #if !defined(NDEBUG)
 std::string Window::GetDebugInfo() const {
   return base::StringPrintf(
       "%s<%d> bounds(%d, %d, %d, %d) %s %s opacity=%.1f",
       name().empty() ? "Unknown" : name().c_str(), id(),
       bounds().x(), bounds().y(), bounds().width(), bounds().height(),
@@ skipping 635 matching lines @@
       return window;
     if (offset)
       *offset += window->bounds().OffsetFromOrigin();
   }
   if (offset)
     *offset = gfx::Vector2d();
   return NULL;
 }
 
 }  // namespace aura