Send the device scale factor from Windows 8 ASH during initialization via the MetroViewerHostMsg_Se…

win8/metro_driver/display_properties.cc

 // Copyright 2013 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 "stdafx.h"
 
 #include <windows.h>
 #include <wrl\implements.h>
 #include <wrl\wrappers\corewrappers.h>
 #include <windows.foundation.h>
 #include <windows.graphics.display.h>
 #include "base/win/scoped_com_initializer.h"
+#include "ui/gfx/win/dpi.h"
 #include "winrt_utils.h"
 
-#pragma comment(lib, "runtimeobject.lib")
-
-extern "C" {
-
-__declspec(dllexport) float GetModernUIScale() {
+float GetModernUIScale() {
   base::win::ScopedCOMInitializer com_init;

[cpu_(ooo_6.6-7.5), 2014/05/08 21:42:37]

is com not initialized ? I think it is.

[ananta, 2014/05/08 22:51:43]

Done.

   Microsoft::WRL::ComPtr<
       ABI::Windows::Graphics::Display::IDisplayPropertiesStatics>
       display_properties;
   if (SUCCEEDED(winrt_utils::CreateActivationFactory(
       RuntimeClass_Windows_Graphics_Display_DisplayProperties,
       display_properties.GetAddressOf()))) {
     ABI::Windows::Graphics::Display::ResolutionScale resolution_scale;
     if (SUCCEEDED(display_properties->get_ResolutionScale(&resolution_scale)))
       return static_cast<float>(resolution_scale) / 100.0f;
   }
   return 1.0f;
 }
-
-}