Drag image should always use the real device scale factor

third_party/WebKit/Source/core/loader/EmptyClients.h

Index: third_party/WebKit/Source/core/loader/EmptyClients.h
diff --git a/third_party/WebKit/Source/core/loader/EmptyClients.h b/third_party/WebKit/Source/core/loader/EmptyClients.h
index c4084d3f33d6a014fb72a92c03cdf46c48b53bcc..24ca6f00bce19c8c2d5fae3fe464ba74bd06e7ef 100644
--- a/third_party/WebKit/Source/core/loader/EmptyClients.h
+++ b/third_party/WebKit/Source/core/loader/EmptyClients.h
@@ -138,6 +138,8 @@ public:
     IntRect viewportToScreen(const IntRect& r, const Widget*) const override { return r; }
     float windowToViewportScalar(const float s) const override { return s; }
     WebScreenInfo screenInfo() const override { return WebScreenInfo(); }
+    float nonEmulatedDeviceScaleFactor() const { return 1.0f; }
+
     void contentsSizeChanged(LocalFrame*, const IntSize&) const override {}
 
     void showMouseOverURL(const HitTestResult&) override {}