Cross-process frames should be notified of device scale factor changes.

content/browser/web_contents/web_contents_view.h

Index: content/browser/web_contents/web_contents_view.h
diff --git a/content/browser/web_contents/web_contents_view.h b/content/browser/web_contents/web_contents_view.h
index cbca3845b5d923d6dd85a7e0b4c14f16c6a05457..090ea993d21ceaafa7621611556a09508146e905 100644
--- a/content/browser/web_contents/web_contents_view.h
+++ b/content/browser/web_contents/web_contents_view.h
@@ -14,6 +14,10 @@
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/native_widget_types.h"
 
+namespace blink {
+  struct WebScreenInfo;
+}
+
 namespace content {
 class RenderViewHost;
 class RenderWidgetHost;
@@ -39,6 +43,12 @@ class WebContentsView {
   // dialog boxes.
   virtual gfx::NativeWindow GetTopLevelNativeWindow() const = 0;
 
+  // The following static method is implemented by each platform.
+  static void GetDefaultScreenInfo(blink::WebScreenInfo* results);
+
+  // Gets screen information for the window associated with this view.
+  virtual void GetScreenInfo(blink::WebScreenInfo* web_screen_info) const = 0;
+
   // Computes the rectangle for the native widget that contains the contents of
   // the tab in the screen coordinate system.
   virtual void GetContainerBounds(gfx::Rect* out) const = 0;