Let page zoom affect resolution and -webkit-device-pixel-ratio MQs.

Source/core/page/DOMWindow.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 1236 matching lines @@
     FloatPoint nodePoint(p->x(), p->y());
     nodePoint = node->convertFromPage(nodePoint);
     return DOMPoint::create(nodePoint.x(), nodePoint.y());
 }
 
 double DOMWindow::devicePixelRatio() const
 {
     if (!m_frame)
         return 0.0;
 
-    Page* page = m_frame->page();
-    if (!page)
-        return 0.0;
-
-    if (RuntimeEnabledFeatures::devicePixelRatioIncludesZoomEnabled())
-        return page->deviceScaleFactor() * m_frame->pageZoomFactor();
-
-    return page->deviceScaleFactor();
+    return m_frame->devicePixelRatio();
 }
 
 void DOMWindow::scrollBy(int x, int y) const
 {
     if (!isCurrentlyDisplayedInFrame())
         return;
 
     document()->updateLayoutIgnorePendingStylesheets();
 
     FrameView* view = m_frame->view();
@@ skipping 475 matching lines @@
     return static_cast<DOMWindowLifecycleNotifier*>(LifecycleContext::lifecycleNotifier());
 }
 
 PassOwnPtr<LifecycleNotifier> DOMWindow::createLifecycleNotifier()
 {
     return DOMWindowLifecycleNotifier::create(this);
 }
 
 
 } // namespace WebCore