Set correct viewport size for an out of process iframe.

content/browser/frame_host/cross_process_frame_connector.h

Index: content/browser/frame_host/cross_process_frame_connector.h
diff --git a/content/browser/frame_host/cross_process_frame_connector.h b/content/browser/frame_host/cross_process_frame_connector.h
index 4ab8e0244837e647ad871b0f50c826f2f97912d0..9f0bc84250eff1ec24a31a16566ef00ce674feea 100644
--- a/content/browser/frame_host/cross_process_frame_connector.h
+++ b/content/browser/frame_host/cross_process_frame_connector.h
@@ -94,6 +94,7 @@ class CrossProcessFrameConnector {
       const FrameHostMsg_CompositorFrameSwappedACK_Params& params);
   void OnReclaimCompositorResources(
       const FrameHostMsg_ReclaimCompositorResources_Params& params);
+  void OnInitializeChildFrame(gfx::Rect frame_rect, float scale_factor);
 
   // The RenderFrameHost that routes messages to the parent frame's renderer
   // process.
@@ -105,6 +106,7 @@ class CrossProcessFrameConnector {
   RenderWidgetHostViewChildFrame* view_;
 
   gfx::Rect child_frame_rect_;
+  float device_scale_factor_;
 };
 
 }  // namespace content