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

content/browser/web_contents/web_contents_view_child_frame.cc

Index: content/browser/web_contents/web_contents_view_child_frame.cc
diff --git a/content/browser/web_contents/web_contents_view_child_frame.cc b/content/browser/web_contents/web_contents_view_child_frame.cc
index 78ab6c6d18a5c9d584751bf57640613b3284fca6..1a261933105fcc591f390b652040dc1ac8defdce 100644
--- a/content/browser/web_contents/web_contents_view_child_frame.cc
+++ b/content/browser/web_contents/web_contents_view_child_frame.cc
@@ -47,6 +47,18 @@ gfx::NativeWindow WebContentsViewChildFrame::GetTopLevelNativeWindow() const {
   return GetOuterView()->GetTopLevelNativeWindow();
 }
 
+void WebContentsViewChildFrame::GetScreenInfo(
+    blink::WebScreenInfo* web_screen_info) const {
+  // TODO(wjmaclean): falling back to the default screen info is not what used
+  // to happen in RenderWidgetHostViewChildFrame, but it seems like the right
+  // thing to do. We should keep an eye on this in case the else-clause below
+  // causes problems.
+  if (web_contents_->GetOuterWebContents())
+    GetOuterView()->GetScreenInfo(web_screen_info);
+  else
+    WebContentsView::GetDefaultScreenInfo(web_screen_info);
+}
+
 void WebContentsViewChildFrame::GetContainerBounds(gfx::Rect* out) const {
   RenderWidgetHostView* view = web_contents_->GetRenderWidgetHostView();
   if (view)