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

Source/core/page/DOMWindow.cpp

Index: Source/core/page/DOMWindow.cpp
diff --git a/Source/core/page/DOMWindow.cpp b/Source/core/page/DOMWindow.cpp
index f45e8dfa3cf44f01479d5cdc23cc89e52796bd24..9bb352ecccb1b69e3aac3ec186054fce087f9cbf 100644
--- a/Source/core/page/DOMWindow.cpp
+++ b/Source/core/page/DOMWindow.cpp
@@ -1254,14 +1254,7 @@ 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->resolutionDPPX();
 }
 
 void DOMWindow::scrollBy(int x, int y) const